diff --git a/.github/workflows/master_build.yml b/.github/workflows/master_build.yml
index 9ef4728cb0..824c279845 100644
--- a/.github/workflows/master_build.yml
+++ b/.github/workflows/master_build.yml
@@ -3,114 +3,60 @@ name: Master CI Build
 on: 
   push:
     branches:
-      - master
+      - gha-master-ci
+# FIXME: Change target branch to "master" before merging into "master" branch.
 
 env:
-  #APP_NAME: gpu-frame-player
   APP_NAME: interface
   BUILD_TYPE: Release
-  BUCKET_NAME: hifi-gh-builds
+  BUILD_NUMBER: ${{ github.run_number }}
   CI_BUILD: Github
-  CMAKE_BACKTRACE_URL: https://highfidelity.sp.backtrace.io:6098
-  CMAKE_BACKTRACE_TOKEN: ${{ secrets.backtrace_token }}
-  CMAKE_BACKTRACE_SYMBOLS_TOKEN: ${{ secrets.backtrace_symbols_token }}
   GIT_COMMIT: ${{ github.sha }}
-  HIFI_VCPKG_BOOTSTRAP: true
-  LAUNCHER_HMAC_SECRET: ${{ secrets.launcher_hmac_secret }}
-  OCULUS_APP_ID: '${{ secrets.oculus_app_id }}'
+  # VCPKG did not build well on OSX disabling HIFI_VCPKG_BOOTSTRAP, which invokes a download to a working version of vcpkg
+  # HIFI_VCPKG_BOOTSTRAP: true
   RELEASE_TYPE: PRODUCTION
-  RELEASE_DYNAMODB_V2: ReleaseManager2-ReleaseQueue-prod
+  RELEASE_NUMBER: ${{ github.run_number }}
   STABLE_BUILD: 0
+  UPLOAD_BUCKET: athena-public
 
-
-  # OSX specific variables
+  # OSX-specific variables
   DEVELOPER_DIR: /Applications/Xcode_11.2.app/Contents/Developer
   MACOSX_DEPLOYMENT_TARGET: '10.11'
 
-  # WIN32 specific variables
+  # WIN-specific variables
   PreferredToolArchitecture: X64
 
-# Mac OS
-#PLATFORM_CMAKE_GENERATOR=Xcode
-#PLATFORM_BUILD_ARGUMENTS=--config Release --target package
-#ARTIFACT_EXPRESSION=build/*.dmg,build/*.zip
-
-# Windows 
-#PLATFORM_CMAKE_GENERATOR=Visual Studio 15 2017 Win64
-#PLATFORM_BUILD_ARGUMENTS=--target package --config release
-#ARTIFACT_EXPRESSION=build/*.exe,build/*.zip,*-symbols.zip
-
-# Ubuntu 
-#PLATFORM_CMAKE_GENERATOR=Unix Makefiles
-#PLATFORM_BUILD_ARGUMENTS=--target all -- -j4
-#ARTIFACT_EXPRESSION=build/assignment-client/**,build/domain-server/**,build/ice-server/ice-server,build/tools/ice-client/ice-client,build/tools/ac-client/ac-client,build/tools/oven,build/ext/makefiles/nvtt/project/lib/**,build/ext/makefiles/quazip/project/lib/**
-
-# Android
-# branch: master
-# GA_TRACKING_ID: ${{ secrets.ga_tracking_id }}
-# ANDROID_OAUTH_CLIENT_SECRET=${MASKED_ANDROID_OAUTH_CLIENT_SECRET_NIGHTLY}
-# ANDROID_OAUTH_CLIENT_ID=6c7d2349c0614640150db37457a1f75dce98a28ffe8f14d47f6cfae4de5b262a
-# ANDROID_OAUTH_REDIRECT_URI=https://dev-android-interface.highfidelity.com/auth
-# branch: !master
-# GA_TRACKING_ID=UA-39558647-11
-# ANDROID_OAUTH_CLIENT_SECRET=${MASKED_ANDROID_OAUTH_CLIENT_SECRET_RELEASE}
-# ANDROID_OAUTH_CLIENT_ID= c1063ea5d0b0c405e0c9cd77351328e211a91496a3f25985a99e861f1661db1d
-# ANDROID_OAUTH_REDIRECT_URI=https://android-interface.highfidelity.com/auth
-# ARTIFACT_EXPRESSION=android/*.apk
-# ANDROID_APK_NAME=HighFidelity-Beta-PR${RELEASE_NUMBER}-${GIT_COMMIT_SHORT}.apk
-# ANDROID_BUILT_APK_NAME=interface-debug.apk	
-# ANDROID_APP=interface
-# ANDROID_BUILD_DIR=debug
-# ANDROID_BUILD_TARGET=assembleDebug
-# STABLE_BUILD=0
-
-
-
 jobs:
-  generate_build_number:
-    runs-on: ubuntu-latest
-    steps:
-    - name: Generate build number
-      id: buildnumber
-      uses: highfidelity/build-number@v3
-      with:
-        token: ${{secrets.github_token}}
-    - name: Upload build number
-      uses: actions/upload-artifact@v1
-      with:
-        name: BUILD_NUMBER
-        path: BUILD_NUMBER
-          
   build:
     strategy:
       matrix:
-        os: [windows-latest, macOS-latest]
-        build_type: [full, client]
-        #os: [windows-latest, macOS-latest, ubuntu-latest]
-        # exclude:
-        #   - os: ubuntu-latest
-        #     build_type: client
+        os: [windows-latest, macOS-latest, ubuntu-18.04]
+        # build_type: [full, client]
+        build_type: [full]
+        include:
+          - os: ubuntu-18.04
+            build_type: full
+            apt-dependencies: mesa-common-dev libegl1 libglvnd-dev libdouble-conversion1 libpulse0
+      fail-fast: false
     runs-on: ${{matrix.os}}
-    needs: generate_build_number
     steps:
-    - name: Download build number
-      uses: actions/download-artifact@v1
-      with:
-        name: BUILD_NUMBER
-    - name: Restore build number
-      id: buildnumber
-      uses: highfidelity/build-number@v3
-      with:
-        output_name: RELEASE_NUMBER
-    - name: Configure Build Environment 1
+    - name: Report Build Number
+      shell: bash
+      run: |
+        echo "Build number: $BUILD_NUMBER"
+    - name: Configure build environment 1
       shell: bash
       id: buildenv1
       run: |
         echo ::set-env name=UPLOAD_PREFIX::master
         echo ::set-env name=GIT_COMMIT_SHORT::`echo $GIT_COMMIT | cut -c1-7`
+        echo ::set-env name=JOB_NAME::"build (${{matrix.os}}, ${{matrix.build_type}})"
         # Linux build variables
-        if [ "${{ matrix.os }}" = "ubuntu-latest" ]; then
+        if [[ "${{ matrix.os }}" = "ubuntu-"* ]]; then
+          echo ::set-env name=PYTHON_EXEC::python3
           echo ::set-env name=INSTALLER_EXT::tgz
+          echo ::set-env name=CMAKE_BUILD_EXTRA::"-- -j3"
+          echo ::set-env name=CMAKE_EXTRA::"-DBUILD_TOOLS:BOOLEAN=FALSE -DHIFI_PYTHON_EXEC:FILEPATH=$(which python3)"
         fi
         # Mac build variables
         if [ "${{ matrix.os }}" = "macOS-latest" ]; then
@@ -118,8 +64,8 @@ jobs:
           echo ::set-env name=ZIP_COMMAND::zip
           echo ::set-env name=ZIP_ARGS::-r
           echo ::set-env name=INSTALLER_EXT::dmg
-          echo ::set-env name=SYMBOL_REGEX::dSYM
-          echo "::set-output name=symbols_archive::${{ steps.buildnumber.outputs.build_number }}-${{ matrix.build_type }}-mac-symbols.zip"
+          echo ::set-env name=CMAKE_EXTRA::"-DCMAKE_XCODE_ATTRIBUTE_CODE_SIGNING_REQUIRED=OFF -DOPENSSL_ROOT_DIR=/usr/local/opt/openssl -G Xcode"
+          echo "::set-output name=symbols_archive::${BUILD_NUMBER}-${{ matrix.build_type }}-mac-symbols.zip"
         fi
         # Windows build variables
         if [ "${{ matrix.os }}" = "windows-latest" ]; then
@@ -127,40 +73,28 @@ jobs:
           echo ::set-env name=ZIP_COMMAND::7z
           echo ::set-env name=ZIP_ARGS::a
           echo ::set-env name=INSTALLER_EXT::exe
+          echo ::set-env name=CMAKE_EXTRA::"-A x64"
           echo "::set-env name=SYMBOL_REGEX::\(exe\|dll\|pdb\)"
-          echo "::set-output name=symbols_archive::${{ steps.buildnumber.outputs.build_number }}-${{ matrix.build_type }}-win-symbols.zip"
+          echo "::set-output name=symbols_archive::${BUILD_NUMBER}-${{ matrix.build_type }}-win-symbols.zip"
+          # echo ::set-env name=HF_PFX_PASSPHRASE::${{secrets.pfx_key}}
+          # echo "::set-env name=HF_PFX_FILE::${{runner.workspace}}\build\codesign.pfx"
         fi
     # Configuration is broken into two steps because you can't set an env var and also reference it in the same step
-    - name: Configure Build Environment 2
+    - name: Configure build environment 2
       shell: bash
       run: |
         echo "${{ steps.buildenv1.outputs.symbols_archive }}"
-        echo ::set-env name=ARTIFACT_PATTERN::HighFidelity-Beta-*.$INSTALLER_EXT
+        echo ::set-env name=ARTIFACT_PATTERN::Vircadia-Alpha-*.$INSTALLER_EXT
         # Build type variables
         if [ "${{ matrix.build_type }}" = "full" ]; then
           echo ::set-env name=CLIENT_ONLY::FALSE
-          echo ::set-env name=INSTALLER::HighFidelity-Beta-$RELEASE_NUMBER-$GIT_COMMIT_SHORT.$INSTALLER_EXT
+          echo ::set-env name=INSTALLER::Vircadia-Alpha-$BUILD_NUMBER-$GIT_COMMIT_SHORT.$INSTALLER_EXT
         else
           echo ::set-env name=CLIENT_ONLY::TRUE
-          echo ::set-env name=INSTALLER::HighFidelity-Beta-Interface-$RELEASE_NUMBER-$GIT_COMMIT_SHORT.$INSTALLER_EXT
+          echo ::set-env name=INSTALLER::Vircadia-Alpha-Interface-$BUILD_NUMBER-$GIT_COMMIT_SHORT.$INSTALLER_EXT
         fi
-        # Linux build variables
-        if [ "${{ matrix.os }}" = "ubuntu-latest" ]; then
-          echo ::set-env name=PYTHON_EXEC::python3
-          echo ::set-env name=CMAKE_EXTRA::""
-        fi
-        # Mac build variables
-        if [ "${{ matrix.os }}" = "macOS-latest" ]; then
-          echo ::set-env name=CMAKE_EXTRA::"-DCMAKE_XCODE_ATTRIBUTE_CODE_SIGNING_REQUIRED=OFF -DOPENSSL_ROOT_DIR=/usr/local/opt/openssl -G Xcode"
-        fi
-        # Windows build variables
-        if [ "${{ matrix.os }}" = "windows-latest" ]; then
-          echo ::set-env name=CMAKE_EXTRA::"-A x64"
-          echo ::set-env name=HF_PFX_PASSPHRASE::${{secrets.pfx_key}}
-          echo "::set-env name=HF_PFX_FILE::${{runner.workspace}}\build\codesign.pfx"
-        fi          
-    - name: Clear Working Directory
-      if: matrix.os == 'windows-latest'
+    - name: Clear working directory
+      if: startsWith(matrix.os, 'windows')
       shell: bash
       working-directory: ${{runner.workspace}}
       run: rm -rf ./*
@@ -168,89 +102,119 @@ jobs:
       with: 
         submodules: true
         fetch-depth: 1
-    - name: Create Build Directory
-      run: cmake -E make_directory ${{runner.workspace}}/build
-    - name: Decrypt Signing Key (Windows)
-      if: matrix.os == 'windows-latest'
-      working-directory: ${{runner.workspace}}/build
+    - name: Install dependencies
+      if: startsWith(matrix.os, 'ubuntu')
       shell: bash
-      run: gpg --batch --yes -o codesign.pfx --passphrase "${{secrets.gpg_symmetric_key}}" --decrypt $GITHUB_WORKSPACE/tools/ci-scripts/codesign.pfx.gpg
-    - name: Import Signing Key (Windows)
-      if: matrix.os == 'windows-latest'
-      working-directory: ${{runner.workspace}}/build
-      shell: powershell
-      run: | 
-        $mypwd=ConvertTo-SecureString -String ${{ secrets.pfx_key }} -Force -AsPlainText
-        Import-PfxCertificate -Password $mypwd -CertStoreLocation Cert:\CurrentUser\My -FilePath ${{runner.workspace}}\build\codesign.pfx
-        Import-PfxCertificate -Password $mypwd -CertStoreLocation Cert:\LocalMachine\My -FilePath ${{runner.workspace}}\build\codesign.pfx
+      run: |
+        echo "Installing Python Modules:"
+        pip3 install distro || exit 1
+        echo "Updating apt repository index"
+        sudo apt update || exit 1
+        echo "Installing apt packages"
+        sudo apt install -y ${{ matrix.apt-dependencies }} || exit 1
     - name: Install Python modules
-      if: matrix.os != 'ubuntu-latest'
+      if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
       shell: bash
       run: $PYTHON_EXEC -m pip install boto3 PyGithub
+    - name: Create build environment
+      shell: bash
+      run: cmake -E make_directory "${{runner.workspace}}/build"
     - name: Configure CMake
       working-directory: ${{runner.workspace}}/build
       shell: bash
-      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DCLIENT_ONLY:BOOLEAN=$CLIENT_ONLY $CMAKE_EXTRA
-    - name: Build Application
+      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DVCPKG_BUILD_TYPE=release -DCLIENT_ONLY:BOOLEAN=$CLIENT_ONLY -DBYPASS_SIGNING:BOOLEAN=TRUE $CMAKE_EXTRA
+    - name: Build application
       working-directory: ${{runner.workspace}}/build
       shell: bash
-      run: cmake --build . --config $BUILD_TYPE --target $APP_NAME
-    - name: Build Console
+      run: cmake --build . --config $BUILD_TYPE --target $APP_NAME $CMAKE_BUILD_EXTRA
+    - name: Build domain server
       working-directory: ${{runner.workspace}}/build
       shell: bash
-      run: cmake --build . --config $BUILD_TYPE --target packaged-server-console
-    - name: Build Domain Server (FullBuild)
-      if: matrix.build_type == 'full'
-      shell: bash
-      working-directory: ${{runner.workspace}}/build
-      run: cmake --build . --config $BUILD_TYPE --target domain-server
-    - name: Build Assignment Client (FullBuild)
-      if: matrix.build_type == 'full'
-      shell: bash
-      working-directory: ${{runner.workspace}}/build
-      run: cmake --build . --config $BUILD_TYPE --target assignment-client
-    - name: Build Installer
+      run: cmake --build . --config $BUILD_TYPE --target domain-server $CMAKE_BUILD_EXTRA
+    - name: Build assignment client
       working-directory: ${{runner.workspace}}/build
       shell: bash
-      run: cmake --build . --config $BUILD_TYPE --target package
-    - name: Sign Installer (Windows)
-      if: matrix.os == 'windows-latest'
-      shell: powershell
-      working-directory: C:\Program Files (x86)\Windows Kits\10\bin\10.0.18362.0\x64
-      run: .\signtool.exe sign /fd sha256 /f ${{runner.workspace}}\build\codesign.pfx /p ${{secrets.pfx_key}} /tr http://sha256timestamp.ws.symantec.com/sha256/timestamp /td SHA256 ${{runner.workspace}}\build\${env:INSTALLER}
-    - name: Upload Artifact
-      if: matrix.os != 'ubuntu-latest'
+      run: cmake --build . --config $BUILD_TYPE --target assignment-client $CMAKE_BUILD_EXTRA
+    - name: Build console
+      working-directory: ${{runner.workspace}}/build
+      shell: bash
+      run: cmake --build . --config $BUILD_TYPE --target packaged-server-console $CMAKE_BUILD_EXTRA
+    - name: Build installer
+      working-directory: ${{runner.workspace}}/build
+      shell: bash
+      run: |
+        echo "Retry code from https://unix.stackexchange.com/a/137639"
+        function fail {
+          echo $1 >&2
+          exit 1
+        }
+        function retry {
+          local n=1
+          local max=5
+          local delay=15
+          while true; do
+            "$@" && break || {
+              if [[ $n -lt $max ]]; then
+                ((n++))
+                echo "Command failed. Attempt $n/$max:"
+                sleep $delay;
+              else
+                fail "The command has failed after $n attempts."
+              fi
+            }
+          done
+        }
+        retry cmake --build . --config $BUILD_TYPE --target package $CMAKE_BUILD_EXTRA
+    #- name: Sign installer (Windows)
+    #  if: startsWith(matrix.os, 'windows')
+    #  shell: powershell
+    #  working-directory: C:\Program Files (x86)\Windows Kits\10\bin\10.0.18362.0\x64
+    #  run: .\signtool.exe sign /fd sha256 /f ${{runner.workspace}}\build\codesign.pfx /p ${{secrets.pfx_key}} /tr http://sha256timestamp.ws.symantec.com/sha256/timestamp /td SHA256 ${{runner.workspace}}\build\${env:INSTALLER}
+    - name: Output system stats
+      if: ${{ always() }}
+      working-directory: ${{runner.workspace}}/build
+      shell: bash
+      run: |
+        echo "Disk usage:"
+        df -h
+    - name: Output installer logs
+      if: failure() && startsWith(matrix.os, 'windows')
+      shell: bash
+      working-directory: ${{runner.workspace}}/build
+      run: cat ./_CPack_Packages/win64/NSIS/NSISOutput.log
+    - name: Upload artifact
+      if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
       shell: bash
       working-directory: ${{runner.workspace}}/build	
       env:	
         AWS_ACCESS_KEY_ID: ${{ secrets.aws_access_key_id }}
         AWS_SECRET_ACCESS_KEY: ${{ secrets.aws_secret_access_key }}	
       run: $PYTHON_EXEC $GITHUB_WORKSPACE/tools/ci-scripts/upload.py 
-    - name: Archive Symbols
-      if: (matrix.os == 'windows-latest') || (matrix.os == 'macOS-latest')
-      working-directory: ${{runner.workspace}}
-      shell: bash
-      run: |
-        SYMBOLS_TEMP="symbols-temp"
-        mkdir $SYMBOLS_TEMP
-        find "./build" \( -path '*/tools/gpu-frame-player/*' -or -path '*/interface/*' -or -path '*/plugins/*' \) -regex ".*\.$SYMBOL_REGEX" -exec cp -r {} $SYMBOLS_TEMP \;
-        cd $SYMBOLS_TEMP
-        $ZIP_COMMAND $ZIP_ARGS ../${{ steps.buildenv1.outputs.symbols_archive }} .
-    - name: Upload Symbols
-      if: (matrix.os == 'windows-latest') || (matrix.os == 'macOS-latest')
-      working-directory: ${{runner.workspace}}
-      shell: bash
-      run: |
-        curl --data-binary @${{ steps.buildenv1.outputs.symbols_archive }} "$CMAKE_BACKTRACE_URL/post?format=symbols&token=$CMAKE_BACKTRACE_SYMBOLS_TOKEN&upload_file=${{steps.buildenv1.outputs.symbols_archive}}&tag=$RELEASE_NUMBER"
-    # - name: Debug List Symbols
-    #   if: (matrix.os == 'windows-latest') || (matrix.os == 'macOS-latest')
-    #   working-directory: ${{runner.workspace}}
-    #   shell: bash
-    #   run: |
-    #     unzip -v "${{runner.workspace}}/${{ steps.buildenv1.outputs.symbols_archive }}"
-    # - name: Debug Upload Symbols Artifact 
-    #   if: (matrix.os == 'windows-latest') || (matrix.os == 'macOS-latest')
-    #   uses: actions/upload-artifact@v1
-    #   with:
-    #     name: symbols
-    #     path: ${{runner.workspace}}/${{ steps.buildenv1.outputs.symbols_archive }}
+    #- name: Archive symbols
+    #  if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
+    #  working-directory: ${{runner.workspace}}
+    #  shell: bash
+    #  run: |
+    #    SYMBOLS_TEMP="symbols-temp"
+    #    mkdir $SYMBOLS_TEMP
+    #    find "./build" \( -path '*/tools/gpu-frame-player/*' -or -path '*/interface/*' -or -path '*/plugins/*' \) -regex ".*\.$SYMBOL_REGEX" -exec cp -r {} $SYMBOLS_TEMP \;
+    #    cd $SYMBOLS_TEMP
+    #    $ZIP_COMMAND $ZIP_ARGS ../${{ steps.buildenv1.outputs.symbols_archive }} .
+    #- name: Upload symbols
+    #  if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
+    #  working-directory: ${{runner.workspace}}
+    #  shell: bash
+    #  run: |
+    #    curl --data-binary @${{ steps.buildenv1.outputs.symbols_archive }} "$CMAKE_BACKTRACE_URL/post?format=symbols&token=$CMAKE_BACKTRACE_SYMBOLS_TOKEN&upload_file=${{steps.buildenv1.outputs.symbols_archive}}&tag=$BUILD_NUMBER"
+    #- name: Debug list symbols
+    #  if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
+    #  working-directory: ${{runner.workspace}}
+    #  shell: bash
+    #  run: |
+    #    unzip -v "${{runner.workspace}}/${{ steps.buildenv1.outputs.symbols_archive }}"
+    #- name: Upload debug list symbols
+    #  if: startsWith(matrix.os, 'windows') || startsWith(matrix.os, 'macOS')
+    #  uses: actions/upload-artifact@v1
+    #  with:
+    #    name: symbols
+    #    path: ${{runner.workspace}}/${{ steps.buildenv1.outputs.symbols_archive }}
diff --git a/assignment-client/src/scripts/EntityScriptServer.cpp b/assignment-client/src/scripts/EntityScriptServer.cpp
index 065ab12abc..16931e8c26 100644
--- a/assignment-client/src/scripts/EntityScriptServer.cpp
+++ b/assignment-client/src/scripts/EntityScriptServer.cpp
@@ -470,7 +470,9 @@ void EntityScriptServer::resetEntitiesScriptEngine() {
     scriptEngines->runScriptInitializers(newEngine);
     newEngine->runInThread();
     auto newEngineSP = qSharedPointerCast<EntitiesScriptEngineProvider>(newEngine);
-    DependencyManager::get<EntityScriptingInterface>()->setEntitiesScriptEngine(newEngineSP);
+    // On the entity script server, these are the same
+    DependencyManager::get<EntityScriptingInterface>()->setPersistentEntitiesScriptEngine(newEngineSP);
+    DependencyManager::get<EntityScriptingInterface>()->setNonPersistentEntitiesScriptEngine(newEngineSP);
 
     if (_entitiesScriptEngine) {
         disconnect(_entitiesScriptEngine.data(), &ScriptEngine::entityScriptDetailsUpdated,
diff --git a/cmake/templates/NSIS.template.in b/cmake/templates/NSIS.template.in
index 013eb98f84..752fb25d20 100644
--- a/cmake/templates/NSIS.template.in
+++ b/cmake/templates/NSIS.template.in
@@ -202,9 +202,9 @@
     ; The Inner invocation has written an uninstaller binary for us.
     ; We need to sign it if it's a production or PR build.
     !if @PRODUCTION_BUILD@ == 1
-      !if @BYPASS_SIGNING@ == 1
+      !if @BYPASS_SIGNING@ == TRUE
         !warning "BYPASS_SIGNING set - installer will not be signed"
-      !else
+      !else 
         !system '"@SIGNTOOL_EXECUTABLE@" sign /fd sha256 /f %HF_PFX_FILE% /p %HF_PFX_PASSPHRASE% /tr http://timestamp.comodoca.com?td=sha256 /td SHA256 $%TEMP%\@UNINSTALLER_NAME@' = 0
       !endif
     !endif
diff --git a/domain-server/resources/web/settings/js/settings.js b/domain-server/resources/web/settings/js/settings.js
index 18d07fa6ef..ea38a30f49 100644
--- a/domain-server/resources/web/settings/js/settings.js
+++ b/domain-server/resources/web/settings/js/settings.js
@@ -365,7 +365,7 @@ $(document).ready(function(){
       confirmButtonText: "Create",
       closeOnConfirm: false,
       html: true
-    }, function(inputValue){
+    }, function (inputValue) {
       if (inputValue === false) {
         swal.close();
 
@@ -375,7 +375,7 @@ $(document).ready(function(){
         }
       } else {
         // we're going to change the alert to a new one with a spinner while we create this domain
-        showSpinnerAlert('Creating domain ID');
+        // showSpinnerAlert('Creating domain ID');
         createNewDomainID(inputValue, justConnected);
       }
     });
@@ -387,7 +387,12 @@ $(document).ready(function(){
       "label": label
     }
 
-    $.post("/api/domains", domainJSON, function(data){
+    $.post("/api/domains", domainJSON, function(data) {
+      if (data.status === "failure") {
+        failedToCreateDomainID(data, justConnected);
+        return;
+      }
+
       // we successfully created a domain ID, set it on that field
       var domainID = data.domain.domainId;
       console.log("Setting domain id to ", data, domainID);
@@ -408,40 +413,50 @@ $(document).ready(function(){
         text: successText,
         html: true,
         confirmButtonText: 'Save'
-      }, function(){
+      }, function () {
         saveSettings();
       });
-    }, 'json').fail(function(){
+    }, 'json').fail(function (data) {
+      failedToCreateDomainID(data, justConnected);
+    });
+  }
+  
+  function failedToCreateDomainID(data, justConnected) {
+    var errorText = "There was a problem creating your new domain ID. Do you want to try again or";
 
-      var errorText = "There was a problem creating your new domain ID. Do you want to try again or";
+    if (data && data.status === "failure") {
+      errorText = "Error: " + data.error + "</br>Do you want to try again or";
+      console.log("Error: " + data.error);
+    } else {
+      console.log("Error: Failed to post to metaverse.");
+    }
 
-      if (justConnected) {
-        errorText += " just save your new access token?</br></br>You can always create a new domain ID later.";
+    if (justConnected) {
+      errorText += " just save your new access token?</br></br>You can always create a new domain ID later.";
+    } else {
+      errorText += " cancel?"
+    }
+
+    // we failed to create the new domain ID, show a sweet-alert that lets them try again or cancel
+    swal({
+      title: '',
+      type: 'error',
+      text: errorText,
+      html: true,
+      confirmButtonText: 'Try again',
+      showCancelButton: true,
+      closeOnConfirm: false
+    }, function (isConfirm) {
+      if (isConfirm) {
+        // they want to try creating a domain ID again
+        showDomainCreationAlert(justConnected);
       } else {
-        errorText += " cancel?"
-      }
-
-      // we failed to create the new domain ID, show a sweet-alert that lets them try again or cancel
-      swal({
-        title: '',
-        type: 'error',
-        text: errorText,
-        html: true,
-        confirmButtonText: 'Try again',
-        showCancelButton: true,
-        closeOnConfirm: false
-      }, function(isConfirm){
-        if (isConfirm) {
-          // they want to try creating a domain ID again
-          showDomainCreationAlert(justConnected);
-        } else {
-          // they want to cancel
-          if (justConnected) {
-            // since they just connected we need to save the access token here
-            saveSettings();
-          }
+        // they want to cancel
+        if (justConnected) {
+          // since they just connected we need to save the access token here
+          saveSettings();
         }
-      });
+      }
     });
   }
 
diff --git a/domain-server/src/DomainGatekeeper.cpp b/domain-server/src/DomainGatekeeper.cpp
index 18926fc805..7126c525bc 100644
--- a/domain-server/src/DomainGatekeeper.cpp
+++ b/domain-server/src/DomainGatekeeper.cpp
@@ -1238,7 +1238,7 @@ void DomainGatekeeper::requestDomainUser(const QString& username, const QString&
 
     // Get data pertaining to "me", the user who generated the access token.
     const QString WORDPRESS_USER_ROUTE = "wp/v2/users/me";
-    const QString WORDPRESS_USER_QUERY = "_fields=username,roles";
+    const QString WORDPRESS_USER_QUERY = "_fields=username,email,roles";
     QUrl domainUserURL = apiBase + WORDPRESS_USER_ROUTE + (apiBase.contains("?") ? "&" : "?") + WORDPRESS_USER_QUERY;
 
     QNetworkRequest request;
@@ -1270,8 +1270,13 @@ void DomainGatekeeper::requestDomainUserFinished() {
     if (200 <= httpStatus && httpStatus < 300) {
 
         QString username = rootObject.value("username").toString().toLower();
-        if (_inFlightDomainUserIdentityRequests.contains(username)) {
+        QString email = rootObject.value("email").toString().toLower();
+
+        if (_inFlightDomainUserIdentityRequests.contains(username) || _inFlightDomainUserIdentityRequests.contains(email)) {
             // Success! Verified user.
+            if (!_inFlightDomainUserIdentityRequests.contains(username)) {
+                username = email;
+            }
             _verifiedDomainUserIdentities.insert(username, _inFlightDomainUserIdentityRequests.value(username));
             _inFlightDomainUserIdentityRequests.remove(username);
 
diff --git a/interface/resources/qml/LoginDialog/LinkAccountBody.qml b/interface/resources/qml/LoginDialog/LinkAccountBody.qml
index 694fd6158f..a4d05d9bc4 100644
--- a/interface/resources/qml/LoginDialog/LinkAccountBody.qml
+++ b/interface/resources/qml/LoginDialog/LinkAccountBody.qml
@@ -114,7 +114,7 @@ Item {
         displayNameField.placeholderText = "Display Name (optional)";
         var savedDisplayName = Settings.getValue("Avatar/displayName", "");
         displayNameField.text = savedDisplayName;
-        emailField.placeholderText = (!isLoggingInToDomain) ? "Username or Email" : "Username";
+        emailField.placeholderText = "Username or Email";
         if (!isLoggingInToDomain) {
             var savedUsername = Settings.getValue("keepMeLoggedIn/savedUsername", "");
             emailField.text = keepMeLoggedInCheckbox.checked ? savedUsername === "Unknown user" ? "" : savedUsername : "";
diff --git a/interface/resources/qml/hifi/dialogs/security/Security.qml b/interface/resources/qml/hifi/dialogs/security/Security.qml
index 1da20838b6..918a0a2ca6 100644
--- a/interface/resources/qml/hifi/dialogs/security/Security.qml
+++ b/interface/resources/qml/hifi/dialogs/security/Security.qml
@@ -312,9 +312,9 @@ Rectangle {
                             parent.color = hifi.colors.blueHighlight;
                         }
                         onClicked: {
-                            lightboxPopup.titleText = "Script Plugin Infrastructure by Kasen";
+                            lightboxPopup.titleText = "Script Plugin Infrastructure";
                             lightboxPopup.bodyText = "Toggles the activation of scripting plugins in the 'plugins/scripting' folder. \n\n"
-                              + "Created by https://kasen.io/";
+                              + "Created by:\n    humbletim@gmail.com\n    kasenvr@gmail.com";
                             lightboxPopup.button1text = "OK";
                             lightboxPopup.button1method = function() {
                                 lightboxPopup.visible = false;
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index b76e3f8dca..c1f972eb30 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -355,6 +355,7 @@ static const QString DESKTOP_DISPLAY_PLUGIN_NAME = "Desktop";
 static const QString ACTIVE_DISPLAY_PLUGIN_SETTING_NAME = "activeDisplayPlugin";
 static const QString SYSTEM_TABLET = "com.highfidelity.interface.tablet.system";
 static const QString KEEP_ME_LOGGED_IN_SETTING_NAME = "keepMeLoggedIn";
+static const QString CACHEBUST_SCRIPT_REQUIRE_SETTING_NAME = "cachebustScriptRequire";
 
 static const float FOCUS_HIGHLIGHT_EXPANSION_FACTOR = 1.05f;
 
@@ -1966,6 +1967,8 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer, bo
     loadSettings();
 
     updateVerboseLogging();
+    
+    setCachebustRequire();
 
     // Make sure we don't time out during slow operations at startup
     updateHeartbeat();
@@ -2600,6 +2603,16 @@ void Application::updateVerboseLogging() {
     QLoggingCategory::setFilterRules(rules);
 }
 
+void Application::setCachebustRequire() {
+    auto menu = Menu::getInstance();
+    if (!menu) {
+        return;
+    }
+    bool enable = menu->isOptionChecked(MenuOption::CachebustRequire);
+    
+    Setting::Handle<bool>{ CACHEBUST_SCRIPT_REQUIRE_SETTING_NAME, false }.set(enable);
+}
+
 void Application::domainConnectionRefused(const QString& reasonMessage, int reasonCodeInt, const QString& extraInfo) {
     DomainHandler::ConnectionRefusedReason reasonCode = static_cast<DomainHandler::ConnectionRefusedReason>(reasonCodeInt);
 
diff --git a/interface/src/Application.h b/interface/src/Application.h
index 16dadc8bf0..5cb5fdd5c0 100644
--- a/interface/src/Application.h
+++ b/interface/src/Application.h
@@ -472,6 +472,8 @@ public slots:
     void setIsInterstitialMode(bool interstitialMode);
 
     void updateVerboseLogging();
+    
+    void setCachebustRequire();
 
     void changeViewAsNeeded(float boomLength);
 
diff --git a/interface/src/Menu.cpp b/interface/src/Menu.cpp
index e175309f06..19cc7eacaa 100644
--- a/interface/src/Menu.cpp
+++ b/interface/src/Menu.cpp
@@ -4,14 +4,14 @@
 //
 //  Created by Stephen Birarda on 8/12/13.
 //  Copyright 2013 High Fidelity, Inc.
+//  Copyright 2020 Vircadia contributors.
 //
 //  Distributed under the Apache License, Version 2.0.
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
 //
-
-// For happ(ier) development of QML, use these two things:
-// This forces QML files to be pulled from the source as you edit it: set environment variable HIFI_USE_SOURCE_TREE_RESOURCES=1
-// Use this to live reload: DependencyManager::get<OffscreenUi>()->clearCache();
+//  For happ(ier) development of QML, use these two things:
+//  This forces QML files to be pulled from the source as you edit it: set environment variable HIFI_USE_SOURCE_TREE_RESOURCES=1
+//  Use this to live reload: DependencyManager::get<OffscreenUi>()->clearCache();
 
 #include "Menu.h"
 #include <QDesktopServices>
@@ -365,6 +365,10 @@ Menu::Menu() {
     // Developer > Scripting > Verbose Logging
     addCheckableActionToQMenuAndActionHash(scriptingOptionsMenu, MenuOption::VerboseLogging, 0, false,
                                            qApp, SLOT(updateVerboseLogging()));
+                                           
+   // Developer > Scripting > Enable Cachebusting of Script.require
+   addCheckableActionToQMenuAndActionHash(scriptingOptionsMenu, MenuOption::CachebustRequire, 0, false,
+                                          qApp, SLOT(setCachebustRequire()));
 
     // Developer > Scripting > Enable Speech Control API
 #if defined(Q_OS_MAC) || defined(Q_OS_WIN)
diff --git a/interface/src/Menu.h b/interface/src/Menu.h
index d33b3b0f5e..cac8e77f9e 100644
--- a/interface/src/Menu.h
+++ b/interface/src/Menu.h
@@ -4,6 +4,7 @@
 //
 //  Created by Stephen Birarda on 8/12/13.
 //  Copyright 2013 High Fidelity, Inc.
+//  Copyright 2020 Vircadia contributors.
 //
 //  Distributed under the Apache License, Version 2.0.
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
@@ -54,6 +55,7 @@ namespace MenuOption {
     const QString BookmarkAvatarEntities = "Bookmark Avatar Entities";
     const QString BookmarkLocation = "Bookmark Location";
     const QString CalibrateCamera = "Calibrate Camera";
+    const QString CachebustRequire = "Enable Cachebusting of Script.require";
     const QString CenterPlayerInView = "Center Player In View";
     const QString Chat = "Chat...";
     const QString ClearDiskCaches = "Clear Disk Caches (requires restart)";
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index b5ed4b767d..2f9c8c4b3a 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -158,79 +158,98 @@ render::ItemID EntityTreeRenderer::renderableIdForEntityId(const EntityItemID& i
 
 int EntityTreeRenderer::_entitiesScriptEngineCount = 0;
 
-void EntityTreeRenderer::resetEntitiesScriptEngine() {
-    _entitiesScriptEngine = scriptEngineFactory(ScriptEngine::ENTITY_CLIENT_SCRIPT, NO_SCRIPT,
-                                                QString("about:Entities %1").arg(++_entitiesScriptEngineCount));
-    DependencyManager::get<ScriptEngines>()->runScriptInitializers(_entitiesScriptEngine);
-    _entitiesScriptEngine->runInThread();
-    auto entitiesScriptEngineProvider = qSharedPointerCast<EntitiesScriptEngineProvider>(_entitiesScriptEngine);
+void EntityTreeRenderer::setupEntityScriptEngineSignals(const ScriptEnginePointer& scriptEngine) {
     auto entityScriptingInterface = DependencyManager::get<EntityScriptingInterface>();
-    entityScriptingInterface->setEntitiesScriptEngine(entitiesScriptEngineProvider);
 
-    // Connect mouse events to entity script callbacks
-    if (!_mouseAndPreloadSignalHandlersConnected) {
-    
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::mousePressOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "mousePressOnEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseDoublePressOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "mouseDoublePressOnEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseMoveOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "mouseMoveOnEntity", event);
-            // FIXME: this is a duplicate of mouseMoveOnEntity, but it seems like some scripts might use this naming
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "mouseMoveEvent", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseReleaseOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "mouseReleaseOnEntity", event);
-        });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::mousePressOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "mousePressOnEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseDoublePressOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "mouseDoublePressOnEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseMoveOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "mouseMoveOnEntity", event);
+        // FIXME: this is a duplicate of mouseMoveOnEntity, but it seems like some scripts might use this naming
+        scriptEngine->callEntityScriptMethod(entityID, "mouseMoveEvent", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::mouseReleaseOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "mouseReleaseOnEntity", event);
+    });
 
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::clickDownOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "clickDownOnEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::holdingClickOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "holdingClickOnEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::clickReleaseOnEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "clickReleaseOnEntity", event);
-        });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::clickDownOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "clickDownOnEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::holdingClickOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "holdingClickOnEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::clickReleaseOnEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "clickReleaseOnEntity", event);
+    });
 
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverEnterEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "hoverEnterEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverOverEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "hoverOverEntity", event);
-        });
-        connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverLeaveEntity, _entitiesScriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "hoverLeaveEntity", event);
-        });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverEnterEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "hoverEnterEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverOverEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "hoverOverEntity", event);
+    });
+    connect(entityScriptingInterface.data(), &EntityScriptingInterface::hoverLeaveEntity, scriptEngine.data(), [&](const EntityItemID& entityID, const PointerEvent& event) {
+        scriptEngine->callEntityScriptMethod(entityID, "hoverLeaveEntity", event);
+    });
 
-        connect(_entitiesScriptEngine.data(), &ScriptEngine::entityScriptPreloadFinished, [&](const EntityItemID& entityID) {
-            EntityItemPointer entity = getTree()->findEntityByID(entityID);
-            if (entity) {
-                entity->setScriptHasFinishedPreload(true);
-            }
-        });
+    connect(scriptEngine.data(), &ScriptEngine::entityScriptPreloadFinished, [&](const EntityItemID& entityID) {
+        EntityItemPointer entity = getTree()->findEntityByID(entityID);
+        if (entity) {
+            entity->setScriptHasFinishedPreload(true);
+        }
+    });
+}
 
-        _mouseAndPreloadSignalHandlersConnected = true;
+void EntityTreeRenderer::resetPersistentEntitiesScriptEngine() {
+    if (_persistentEntitiesScriptEngine) {
+        _persistentEntitiesScriptEngine->unloadAllEntityScripts(true);
+        _persistentEntitiesScriptEngine->stop();
+        _persistentEntitiesScriptEngine->waitTillDoneRunning();
+        _persistentEntitiesScriptEngine->disconnectNonEssentialSignals();
     }
+    _persistentEntitiesScriptEngine = scriptEngineFactory(ScriptEngine::ENTITY_CLIENT_SCRIPT, NO_SCRIPT,
+                                                QString("about:Entities %1").arg(++_entitiesScriptEngineCount));
+    DependencyManager::get<ScriptEngines>()->runScriptInitializers(_persistentEntitiesScriptEngine);
+    _persistentEntitiesScriptEngine->runInThread();
+    auto entitiesScriptEngineProvider = qSharedPointerCast<EntitiesScriptEngineProvider>(_persistentEntitiesScriptEngine);
+    auto entityScriptingInterface = DependencyManager::get<EntityScriptingInterface>();
+    entityScriptingInterface->setPersistentEntitiesScriptEngine(entitiesScriptEngineProvider);
+
+    setupEntityScriptEngineSignals(_persistentEntitiesScriptEngine);
+}
+
+void EntityTreeRenderer::resetNonPersistentEntitiesScriptEngine() {
+    if (_nonPersistentEntitiesScriptEngine) {
+        _nonPersistentEntitiesScriptEngine->unloadAllEntityScripts(false);
+        _nonPersistentEntitiesScriptEngine->stop();
+        _nonPersistentEntitiesScriptEngine->waitTillDoneRunning();
+        _nonPersistentEntitiesScriptEngine->disconnectNonEssentialSignals();
+    }
+    _nonPersistentEntitiesScriptEngine = scriptEngineFactory(ScriptEngine::ENTITY_CLIENT_SCRIPT, NO_SCRIPT,
+                                                QString("about:Entities %1").arg(++_entitiesScriptEngineCount));
+    DependencyManager::get<ScriptEngines>()->runScriptInitializers(_nonPersistentEntitiesScriptEngine);
+    _nonPersistentEntitiesScriptEngine->runInThread();
+    auto entitiesScriptEngineProvider = qSharedPointerCast<EntitiesScriptEngineProvider>(_nonPersistentEntitiesScriptEngine);
+    DependencyManager::get<EntityScriptingInterface>()->setNonPersistentEntitiesScriptEngine(entitiesScriptEngineProvider);
+
+    setupEntityScriptEngineSignals(_nonPersistentEntitiesScriptEngine);
 }
 
 void EntityTreeRenderer::stopDomainAndNonOwnedEntities() {
     leaveDomainAndNonOwnedEntities();
     // unload and stop the engine
-    if (_entitiesScriptEngine) {
-        QList<EntityItemID> entitiesWithEntityScripts = _entitiesScriptEngine->getListOfEntityScriptIDs();
+    if (_nonPersistentEntitiesScriptEngine) {
+        QList<EntityItemID> entitiesWithEntityScripts = _nonPersistentEntitiesScriptEngine->getListOfEntityScriptIDs();
 
-        foreach (const EntityItemID& entityID,  entitiesWithEntityScripts) {
+        foreach (const EntityItemID& entityID, entitiesWithEntityScripts) {
             EntityItemPointer entityItem = getTree()->findEntityByEntityItemID(entityID);
-
             if (entityItem && !entityItem->getScript().isEmpty()) {
                 if (!(entityItem->isLocalEntity() || entityItem->isMyAvatarEntity())) {
-                    if (_currentEntitiesInside.contains(entityID)) {
-                        _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
-                    }
-                    _entitiesScriptEngine->unloadEntityScript(entityID, true);
+                    _nonPersistentEntitiesScriptEngine->unloadEntityScript(entityID, true);
                 }
             }
         }
@@ -240,6 +259,10 @@ void EntityTreeRenderer::stopDomainAndNonOwnedEntities() {
 void EntityTreeRenderer::clearDomainAndNonOwnedEntities() {
     stopDomainAndNonOwnedEntities();
 
+    if (!_shuttingDown && _wantScripts) {
+        resetNonPersistentEntitiesScriptEngine();
+    }
+
     std::unordered_map<EntityItemID, EntityRendererPointer> savedEntities;
     std::unordered_set<EntityRendererPointer> savedRenderables;
     // remove all entities from the scene
@@ -269,16 +292,22 @@ void EntityTreeRenderer::clearDomainAndNonOwnedEntities() {
 
 void EntityTreeRenderer::clear() {
     leaveAllEntities();
-    // unload and stop the engine
-    if (_entitiesScriptEngine) {
-        // do this here (instead of in deleter) to avoid marshalling unload signals back to this thread
-        _entitiesScriptEngine->unloadAllEntityScripts(true);
-        _entitiesScriptEngine->stop();
-    }
 
     // reset the engine
     auto scene = _viewState->getMain3DScene();
     if (_shuttingDown) {
+        // unload and stop the engines
+        if (_nonPersistentEntitiesScriptEngine) {
+            // do this here (instead of in deleter) to avoid marshalling unload signals back to this thread
+            _nonPersistentEntitiesScriptEngine->unloadAllEntityScripts(true);
+            _nonPersistentEntitiesScriptEngine->stop();
+        }
+        if (_persistentEntitiesScriptEngine) {
+            // do this here (instead of in deleter) to avoid marshalling unload signals back to this thread
+            _persistentEntitiesScriptEngine->unloadAllEntityScripts(true);
+            _persistentEntitiesScriptEngine->stop();
+        }
+
         if (scene) {
             render::Transaction transaction;
             for (const auto& entry :  _entitiesInScene) {
@@ -289,7 +318,8 @@ void EntityTreeRenderer::clear() {
         }
     } else {
         if (_wantScripts) {
-            resetEntitiesScriptEngine();
+            resetPersistentEntitiesScriptEngine();
+            resetNonPersistentEntitiesScriptEngine();
         }
         if (scene) {
             for (const auto& entry :  _entitiesInScene) {
@@ -313,13 +343,17 @@ void EntityTreeRenderer::clear() {
 }
 
 void EntityTreeRenderer::reloadEntityScripts() {
-    _entitiesScriptEngine->unloadAllEntityScripts();
-    _entitiesScriptEngine->resetModuleCache();
+    _persistentEntitiesScriptEngine->unloadAllEntityScripts();
+    _persistentEntitiesScriptEngine->resetModuleCache();
+    _nonPersistentEntitiesScriptEngine->unloadAllEntityScripts();
+    _nonPersistentEntitiesScriptEngine->resetModuleCache();
+
     for (const auto& entry : _entitiesInScene) {
         const auto& renderer = entry.second;
         const auto& entity = renderer->getEntity();
-        if (!entity->getScript().isEmpty()) {
-            _entitiesScriptEngine->loadEntityScript(entity->getEntityItemID(), resolveScriptURL(entity->getScript()), true);
+        if (entity && !entity->getScript().isEmpty()) {
+            auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+            scriptEngine->loadEntityScript(entity->getEntityItemID(), resolveScriptURL(entity->getScript()), true);
         }
     }
 }
@@ -329,7 +363,8 @@ void EntityTreeRenderer::init() {
     EntityTreePointer entityTree = std::static_pointer_cast<EntityTree>(_tree);
 
     if (_wantScripts) {
-        resetEntitiesScriptEngine();
+        resetPersistentEntitiesScriptEngine();
+        resetNonPersistentEntitiesScriptEngine();
     }
 
     forceRecheckEntities(); // setup our state to force checking our inside/outsideness of entities
@@ -341,8 +376,11 @@ void EntityTreeRenderer::init() {
 }
 
 void EntityTreeRenderer::shutdown() {
-    if (_entitiesScriptEngine) {
-        _entitiesScriptEngine->disconnectNonEssentialSignals(); // disconnect all slots/signals from the script engine, except essential
+    if (_persistentEntitiesScriptEngine) {
+        _persistentEntitiesScriptEngine->disconnectNonEssentialSignals(); // disconnect all slots/signals from the script engine, except essential
+    }
+    if (_nonPersistentEntitiesScriptEngine) {
+        _nonPersistentEntitiesScriptEngine->disconnectNonEssentialSignals(); // disconnect all slots/signals from the script engine, except essential
     }
     _shuttingDown = true;
 
@@ -658,12 +696,16 @@ void EntityTreeRenderer::checkEnterLeaveEntities() {
             // EntityItemIDs from here. The callEntityScriptMethod() method is robust against attempting to call scripts
             // for entity IDs that no longer exist.
 
-            if (_entitiesScriptEngine) {
+            if (_persistentEntitiesScriptEngine && _nonPersistentEntitiesScriptEngine) {
                 // for all of our previous containing entities, if they are no longer containing then send them a leave event
                 foreach(const EntityItemID& entityID, _currentEntitiesInside) {
                     if (!entitiesContainingAvatar.contains(entityID)) {
                         emit leaveEntity(entityID);
-                        _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+                        auto entity = getTree()->findEntityByEntityItemID(entityID);
+                        if (entity) {
+                            auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+                            scriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+                        }
                     }
                 }
 
@@ -671,7 +713,11 @@ void EntityTreeRenderer::checkEnterLeaveEntities() {
                 foreach(const EntityItemID& entityID, entitiesContainingAvatar) {
                     if (!_currentEntitiesInside.contains(entityID)) {
                         emit enterEntity(entityID);
-                        _entitiesScriptEngine->callEntityScriptMethod(entityID, "enterEntity");
+                        auto entity = getTree()->findEntityByEntityItemID(entityID);
+                        if (entity) {
+                            auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+                            scriptEngine->callEntityScriptMethod(entityID, "enterEntity");
+                        }
                     }
                 }
                 _currentEntitiesInside = entitiesContainingAvatar;
@@ -687,8 +733,8 @@ void EntityTreeRenderer::leaveDomainAndNonOwnedEntities() {
             EntityItemPointer entityItem = getTree()->findEntityByEntityItemID(entityID);
             if (entityItem && !(entityItem->isLocalEntity() || entityItem->isMyAvatarEntity())) {
                 emit leaveEntity(entityID);
-                if (_entitiesScriptEngine) {
-                    _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+                if (_nonPersistentEntitiesScriptEngine) {
+                    _nonPersistentEntitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
                 }
             } else {
                 currentEntitiesInsideToSave.insert(entityID);
@@ -706,8 +752,12 @@ void EntityTreeRenderer::leaveAllEntities() {
         // for all of our previous containing entities, if they are no longer containing then send them a leave event
         foreach(const EntityItemID& entityID, _currentEntitiesInside) {
             emit leaveEntity(entityID);
-            if (_entitiesScriptEngine) {
-                _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+            EntityItemPointer entityItem = getTree()->findEntityByEntityItemID(entityID);
+            if (entityItem) {
+                auto& scriptEngine = (entityItem->isLocalEntity() || entityItem->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+                if (scriptEngine) {
+                    scriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+                }
             }
         }
         _currentEntitiesInside.clear();
@@ -1003,11 +1053,12 @@ void EntityTreeRenderer::deletingEntity(const EntityItemID& entityID) {
         return;
     }
 
-    if (_tree && !_shuttingDown && _entitiesScriptEngine && !itr->second->getEntity()->getScript().isEmpty()) {
+    auto& scriptEngine = (itr->second->getEntity()->isLocalEntity() || itr->second->getEntity()->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+    if (_tree && !_shuttingDown && scriptEngine && !itr->second->getEntity()->getScript().isEmpty()) {
         if (_currentEntitiesInside.contains(entityID)) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+            scriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
         }
-        _entitiesScriptEngine->unloadEntityScript(entityID, true);
+        scriptEngine->unloadEntityScript(entityID, true);
     }
 
     auto scene = _viewState->getMain3DScene();
@@ -1052,20 +1103,21 @@ void EntityTreeRenderer::checkAndCallPreload(const EntityItemID& entityID, bool
         if (!entity) {
             return;
         }
-        bool shouldLoad = entity->shouldPreloadScript() && _entitiesScriptEngine;
+        auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+        bool shouldLoad = entity->shouldPreloadScript() && scriptEngine;
         QString scriptUrl = entity->getScript();
         if ((shouldLoad && unloadFirst) || scriptUrl.isEmpty()) {
-            if (_entitiesScriptEngine) {
+            if (scriptEngine) {
                 if (_currentEntitiesInside.contains(entityID)) {
-                    _entitiesScriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
+                    scriptEngine->callEntityScriptMethod(entityID, "leaveEntity");
                 }
-                _entitiesScriptEngine->unloadEntityScript(entityID);
+                scriptEngine->unloadEntityScript(entityID);
             }
             entity->scriptHasUnloaded();
         }
         if (shouldLoad) {
             entity->setScriptHasFinishedPreload(false);
-            _entitiesScriptEngine->loadEntityScript(entityID, resolveScriptURL(scriptUrl), reload);
+            scriptEngine->loadEntityScript(entityID, resolveScriptURL(scriptUrl), reload);
             entity->scriptHasPreloaded();
         }
     }
@@ -1172,8 +1224,9 @@ void EntityTreeRenderer::entityCollisionWithEntity(const EntityItemID& idA, cons
         if ((myNodeID == entityASimulatorID && entityAIsDynamic) || (myNodeID == entityBSimulatorID && (!entityAIsDynamic || entityASimulatorID.isNull()))) {
             playEntityCollisionSound(entityA, collision);
             emit collisionWithEntity(idA, idB, collision);
-            if (_entitiesScriptEngine) {
-                _entitiesScriptEngine->callEntityScriptMethod(idA, "collisionWithEntity", idB, collision);
+            auto& scriptEngine = (entityA->isLocalEntity() || entityA->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+            if (scriptEngine) {
+                scriptEngine->callEntityScriptMethod(idA, "collisionWithEntity", idB, collision);
             }
         }
 
@@ -1183,8 +1236,9 @@ void EntityTreeRenderer::entityCollisionWithEntity(const EntityItemID& idA, cons
             Collision invertedCollision(collision);
             invertedCollision.invert();
             emit collisionWithEntity(idB, idA, invertedCollision);
-            if (_entitiesScriptEngine) {
-                _entitiesScriptEngine->callEntityScriptMethod(idB, "collisionWithEntity", idA, invertedCollision);
+            auto& scriptEngine = (entityB->isLocalEntity() || entityB->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+            if (scriptEngine) {
+                scriptEngine->callEntityScriptMethod(idB, "collisionWithEntity", idA, invertedCollision);
             }
         }
     }
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.h b/libraries/entities-renderer/src/EntityTreeRenderer.h
index 149b23702f..f7623aad10 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.h
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.h
@@ -173,7 +173,9 @@ private:
     EntityRendererPointer renderableForEntity(const EntityItemPointer& entity) const { return renderableForEntityId(entity->getID()); }
     render::ItemID renderableIdForEntity(const EntityItemPointer& entity) const { return renderableIdForEntityId(entity->getID()); }
 
-    void resetEntitiesScriptEngine();
+    void resetPersistentEntitiesScriptEngine();
+    void resetNonPersistentEntitiesScriptEngine();
+    void setupEntityScriptEngineSignals(const ScriptEnginePointer& scriptEngine);
 
     void findBestZoneAndMaybeContainingEntities(QSet<EntityItemID>& entitiesContainingAvatar);
 
@@ -196,7 +198,8 @@ private:
     QSet<EntityItemID> _currentEntitiesInside;
 
     bool _wantScripts;
-    ScriptEnginePointer _entitiesScriptEngine;
+    ScriptEnginePointer _nonPersistentEntitiesScriptEngine; // used for domain + non-owned avatar entities, cleared on domain switch
+    ScriptEnginePointer _persistentEntitiesScriptEngine; // used for local + owned avatar entities, persists on domain switch, cleared on reload content
 
     void playEntityCollisionSound(const EntityItemPointer& entity, const Collision& collision);
 
@@ -214,8 +217,6 @@ private:
     std::function<RayToEntityIntersectionResult(unsigned int)> _getPrevRayPickResultOperator;
     std::function<void(unsigned int, bool)> _setPrecisionPickingOperator;
 
-    bool _mouseAndPreloadSignalHandlersConnected { false };
-
     class LayeredZone {
     public:
         LayeredZone(std::shared_ptr<ZoneEntityItem> zone) : zone(zone), id(zone->getID()), volume(zone->getVolumeEstimate()) {}
diff --git a/libraries/entities/src/EntityScriptingInterface.cpp b/libraries/entities/src/EntityScriptingInterface.cpp
index 05947551ba..36beb9f0d3 100644
--- a/libraries/entities/src/EntityScriptingInterface.cpp
+++ b/libraries/entities/src/EntityScriptingInterface.cpp
@@ -1046,18 +1046,26 @@ QSizeF EntityScriptingInterface::textSize(const QUuid& id, const QString& text)
     return EntityTree::textSize(id, text);
 }
 
-void EntityScriptingInterface::setEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine) {
+void EntityScriptingInterface::setPersistentEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine) {
     std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
-    _entitiesScriptEngine = engine;
+    _persistentEntitiesScriptEngine = engine;
+}
+
+void EntityScriptingInterface::setNonPersistentEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine) {
+    std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
+    _nonPersistentEntitiesScriptEngine = engine;
 }
 
 void EntityScriptingInterface::callEntityMethod(const QUuid& id, const QString& method, const QStringList& params) {
     PROFILE_RANGE(script_entities, __FUNCTION__);
-
-    std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
-    if (_entitiesScriptEngine) {
-        EntityItemID entityID{ id };
-        _entitiesScriptEngine->callEntityScriptMethod(entityID, method, params);
+    
+    auto entity = getEntityTree()->findEntityByEntityItemID(id);
+    if (entity) {
+        std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
+        auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+        if (scriptEngine) {
+            scriptEngine->callEntityScriptMethod(id, method, params);
+        }
     }
 }
 
@@ -1099,9 +1107,13 @@ void EntityScriptingInterface::handleEntityScriptCallMethodPacket(QSharedPointer
             params << paramString;
         }
 
-        std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
-        if (_entitiesScriptEngine) {
-            _entitiesScriptEngine->callEntityScriptMethod(entityID, method, params, senderNode->getUUID());
+        auto entity = getEntityTree()->findEntityByEntityItemID(entityID);
+        if (entity) {
+            std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
+            auto& scriptEngine = (entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine;
+            if (scriptEngine) {
+                scriptEngine->callEntityScriptMethod(entityID, method, params, senderNode->getUUID());
+            }
         }
     }
 }
@@ -1332,7 +1344,7 @@ bool EntityPropertyMetadataRequest::script(EntityItemID entityID, QScriptValue h
         if (entitiesScriptEngine) {
             request->setFuture(entitiesScriptEngine->getLocalEntityScriptDetails(entityID));
         }
-    });
+    }, entityID);
     if (!request->isStarted()) {
         request->deleteLater();
         callScopedHandlerObject(handler, _engine->makeError("Entities Scripting Provider unavailable", "InternalError"), QScriptValue());
diff --git a/libraries/entities/src/EntityScriptingInterface.h b/libraries/entities/src/EntityScriptingInterface.h
index fca0dad871..14d853fbaf 100644
--- a/libraries/entities/src/EntityScriptingInterface.h
+++ b/libraries/entities/src/EntityScriptingInterface.h
@@ -181,7 +181,8 @@ public:
 
     void setEntityTree(EntityTreePointer modelTree);
     EntityTreePointer getEntityTree() { return _entityTree; }
-    void setEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine);
+    void setPersistentEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine);
+    void setNonPersistentEntitiesScriptEngine(QSharedPointer<EntitiesScriptEngineProvider> engine);
 
     void resetActivityTracking();
     ActivityTracking getActivityTracking() const { return _activityTracking; }
@@ -2510,9 +2511,12 @@ signals:
     void webEventReceived(const EntityItemID& entityItemID, const QVariant& message);
 
 protected:
-    void withEntitiesScriptEngine(std::function<void(QSharedPointer<EntitiesScriptEngineProvider>)> function) {
-        std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
-        function(_entitiesScriptEngine);
+    void withEntitiesScriptEngine(std::function<void(QSharedPointer<EntitiesScriptEngineProvider>)> function, const EntityItemID& id) {
+        auto entity = getEntityTree()->findEntityByEntityItemID(id);
+        if (entity) {
+            std::lock_guard<std::recursive_mutex> lock(_entitiesScriptEngineLock);
+            function((entity->isLocalEntity() || entity->isMyAvatarEntity()) ? _persistentEntitiesScriptEngine : _nonPersistentEntitiesScriptEngine);
+        }
     };
 
 private slots:
@@ -2542,7 +2546,8 @@ private:
     EntityTreePointer _entityTree;
 
     std::recursive_mutex _entitiesScriptEngineLock;
-    QSharedPointer<EntitiesScriptEngineProvider> _entitiesScriptEngine;
+    QSharedPointer<EntitiesScriptEngineProvider> _persistentEntitiesScriptEngine;
+    QSharedPointer<EntitiesScriptEngineProvider> _nonPersistentEntitiesScriptEngine;
 
     bool _bidOnSimulationOwnership { false };
 
diff --git a/libraries/networking/src/FileResourceRequest.cpp b/libraries/networking/src/FileResourceRequest.cpp
index f9ec7797be..ebeb5936c2 100644
--- a/libraries/networking/src/FileResourceRequest.cpp
+++ b/libraries/networking/src/FileResourceRequest.cpp
@@ -13,6 +13,7 @@
 
 #include <QtCore/QFile>
 #include <QtCore/QFileSelector>
+#include <QtCore/QDateTime>
 #include <QtCore/QDebug>
 
 #include <StatTracker.h>
@@ -54,6 +55,7 @@ void FileResourceRequest::doSend() {
     } else {
         QFile file(filename);
         if (file.exists()) {
+            setProperty("last-modified", toHttpDateString(QFileInfo(file).lastModified().toMSecsSinceEpoch()));
             if (file.open(QFile::ReadOnly)) {
 
                 if (file.size() < _byteRange.fromInclusive || file.size() < _byteRange.toExclusive) {
diff --git a/libraries/networking/src/ResourceRequest.cpp b/libraries/networking/src/ResourceRequest.cpp
index c63bd4c563..8739cb61da 100644
--- a/libraries/networking/src/ResourceRequest.cpp
+++ b/libraries/networking/src/ResourceRequest.cpp
@@ -15,8 +15,14 @@
 #include <DependencyManager.h>
 #include <StatTracker.h>
 
+#include <QtCore/QDateTime>
 #include <QtCore/QThread>
 
+QString ResourceRequest::toHttpDateString(uint64_t msecsSinceEpoch) {
+    return QDateTime::fromMSecsSinceEpoch(msecsSinceEpoch)
+        .toString("ddd, dd MMM yyyy hh:mm:ss 'GMT'")
+        .toLatin1();
+}
 
 void ResourceRequest::send() {
     if (QThread::currentThread() != thread()) {
diff --git a/libraries/networking/src/ResourceRequest.h b/libraries/networking/src/ResourceRequest.h
index 550294d79b..042e706291 100644
--- a/libraries/networking/src/ResourceRequest.h
+++ b/libraries/networking/src/ResourceRequest.h
@@ -90,6 +90,7 @@ public:
     void setCacheEnabled(bool value) { _cacheEnabled = value; }
     void setByteRange(ByteRange byteRange) { _byteRange = byteRange; }
 
+    static QString toHttpDateString(uint64_t msecsSinceEpoch);
 public slots:
     void send();
 
diff --git a/libraries/script-engine/src/ScriptCache.cpp b/libraries/script-engine/src/ScriptCache.cpp
index b23aa48762..0b63803a33 100644
--- a/libraries/script-engine/src/ScriptCache.cpp
+++ b/libraries/script-engine/src/ScriptCache.cpp
@@ -85,11 +85,25 @@ void ScriptCache::getScriptContents(const QString& scriptOrURL, contentAvailable
 
     Lock lock(_containerLock);
     if (_scriptCache.contains(url) && !forceDownload) {
-        auto scriptContent = _scriptCache[url];
-        lock.unlock();
-        qCDebug(scriptengine) << "Found script in cache:" << url.fileName();
-        contentAvailable(url.toString(), scriptContent, true, true, STATUS_CACHED);
-    } else {
+        auto entry = _scriptCache[url];
+        if (url.isLocalFile() || url.scheme().isEmpty()) {
+            auto modifiedTime = QFileInfo(url.toLocalFile()).lastModified();
+            QString localTime = ResourceRequest::toHttpDateString(modifiedTime.toMSecsSinceEpoch());
+            QString cachedTime = entry["last-modified"].toString();
+            if (cachedTime != localTime) {
+                forceDownload = true;
+                qCDebug(scriptengine) << "Found script in cache, but local file modified; reloading:" << url.fileName()
+                                      << "(memory:" << cachedTime << "disk:" << localTime << ")";
+            }
+        }
+        if (!forceDownload) {
+            lock.unlock();
+            qCDebug(scriptengine) << "Found script in cache:" << url.fileName();
+            contentAvailable(url.toString(), entry["data"].toString(), true, true, STATUS_CACHED);
+            return;
+        }
+    }
+    {
         auto& scriptRequest = _activeScriptRequests[url];
         bool alreadyWaiting = scriptRequest.scriptUsers.size() > 0;
         scriptRequest.scriptUsers.push_back(contentAvailable);
@@ -140,7 +154,10 @@ void ScriptCache::scriptContentAvailable(int maxRetries) {
 
                 _activeScriptRequests.remove(url);
 
-                _scriptCache[url] = scriptContent = req->getData();
+                _scriptCache[url] = {
+                    { "data", scriptContent = req->getData() },
+                    { "last-modified", req->property("last-modified") },
+                };
             } else {
                 auto result = req->getResult();
                 bool irrecoverable =
@@ -177,7 +194,7 @@ void ScriptCache::scriptContentAvailable(int maxRetries) {
                     allCallbacks = scriptRequest.scriptUsers;
 
                     if (_scriptCache.contains(url)) {
-                        scriptContent = _scriptCache[url];
+                        scriptContent = _scriptCache[url]["data"].toString();
                     }
                     _activeScriptRequests.remove(url);
                     qCWarning(scriptengine) << "Error loading script from URL (" << status <<")";
diff --git a/libraries/script-engine/src/ScriptCache.h b/libraries/script-engine/src/ScriptCache.h
index 511d392409..4ab4458ee9 100644
--- a/libraries/script-engine/src/ScriptCache.h
+++ b/libraries/script-engine/src/ScriptCache.h
@@ -60,7 +60,7 @@ private:
     Mutex _containerLock;
     QMap<QUrl, ScriptRequest> _activeScriptRequests;
     
-    QHash<QUrl, QString> _scriptCache;
+    QHash<QUrl, QVariantMap> _scriptCache;
     QMultiMap<QUrl, ScriptUser*> _scriptUsers;
 };
 
diff --git a/libraries/script-engine/src/ScriptEngine.cpp b/libraries/script-engine/src/ScriptEngine.cpp
index 88c682370c..9480b498ba 100644
--- a/libraries/script-engine/src/ScriptEngine.cpp
+++ b/libraries/script-engine/src/ScriptEngine.cpp
@@ -1941,9 +1941,12 @@ QScriptValue ScriptEngine::require(const QString& moduleId) {
     // modules get cached in `Script.require.cache` and (similar to Node.js) users can access it
     // to inspect particular entries and invalidate them by deleting the key:
     //   `delete Script.require.cache[Script.require.resolve(moduleId)];`
+    
+    // Check to see if we should invalidate the cache based on a user setting.
+    Setting::Handle<bool> getCachebustSetting {"cachebustScriptRequire", false };
 
     // cacheMeta is just used right now to tell deleted keys apart from undefined ones
-    bool invalidateCache = module.isUndefined() && cacheMeta.property(moduleId).isValid();
+    bool invalidateCache = getCachebustSetting.get() || (module.isUndefined() && cacheMeta.property(moduleId).isValid());
 
     // reset the cacheMeta record so invalidation won't apply next time, even if the module fails to load
     cacheMeta.setProperty(modulePath, QScriptValue());
diff --git a/libraries/script-engine/src/ScriptEngine.h b/libraries/script-engine/src/ScriptEngine.h
index 219453875e..8cbeed58af 100644
--- a/libraries/script-engine/src/ScriptEngine.h
+++ b/libraries/script-engine/src/ScriptEngine.h
@@ -4,6 +4,7 @@
 //
 //  Created by Brad Hefta-Gaub on 12/14/13.
 //  Copyright 2013 High Fidelity, Inc.
+//  Copyright 2020 Vircadia contributors.
 //
 //  Distributed under the Apache License, Version 2.0.
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
diff --git a/plugins/CMakeLists.txt b/plugins/CMakeLists.txt
index 1448e14c72..a72371f544 100644
--- a/plugins/CMakeLists.txt
+++ b/plugins/CMakeLists.txt
@@ -53,5 +53,5 @@ set(DIR "opusCodec")
 add_subdirectory(${DIR})
 
 # example plugins
-set(DIR "KasenAPIExample")
+set(DIR "JSAPIExample")
 add_subdirectory(${DIR})
diff --git a/plugins/JSAPIExample/CMakeLists.txt b/plugins/JSAPIExample/CMakeLists.txt
new file mode 100644
index 0000000000..a8fa0a1fd6
--- /dev/null
+++ b/plugins/JSAPIExample/CMakeLists.txt
@@ -0,0 +1,3 @@
+set(TARGET_NAME JSAPIExample)
+setup_hifi_client_server_plugin(scripting)
+link_hifi_libraries(shared plugins)
diff --git a/plugins/JSAPIExample/src/JSAPIExample.cpp b/plugins/JSAPIExample/src/JSAPIExample.cpp
new file mode 100644
index 0000000000..ed637e198b
--- /dev/null
+++ b/plugins/JSAPIExample/src/JSAPIExample.cpp
@@ -0,0 +1,251 @@
+//
+//  JSAPIExample.cpp
+//  plugins/JSAPIExample/src
+//
+//  Copyright (c) 2019-2020 humbletim (humbletim@gmail.com)
+//  Copyright (c) 2019 Kalila L. (kasenvr@gmail.com)
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+
+//  Example of prototyping new JS APIs by leveraging the existing plugin system.
+
+#include <QCoreApplication>
+#include <QtCore/QByteArray>
+#include <QtCore/QDir>
+#include <QtCore/QFileInfo>
+#include <QtCore/QJsonObject>
+#include <QtCore/QLoggingCategory>
+#include <QtCore/QThread>
+#include <QtCore/QTimer>
+#include <QtScript/QScriptEngine>
+#include <QtScript/QScriptable>
+
+#include <SettingHelpers.h>  // for ::settingsFilename()
+#include <SharedUtil.h>      // for ::usecTimestampNow()
+#include <shared/ScriptInitializerMixin.h>
+
+// NOTE: replace this with your own namespace when starting a new plugin (to avoid .so/.dll symbol clashes)
+namespace REPLACE_ME_WITH_UNIQUE_NAME {
+
+    static constexpr auto JSAPI_SEMANTIC_VERSION = "0.0.1";
+    static constexpr auto JSAPI_EXPORT_NAME = "JSAPIExample";
+
+    QLoggingCategory logger { "jsapiexample" };
+
+    inline QVariant raiseScriptingError(QScriptContext* context, const QString& message, const QVariant& returnValue = QVariant()) {
+        if (context) {
+            // when a QScriptContext is available throw an actual JS Exception (which can be caught using try/catch on JS side)
+            context->throwError(message);
+        } else {
+            // otherwise just log the error
+            qCWarning(logger) << "error:" << message;
+        }
+        return returnValue;
+    }
+
+    QObject* createScopedSettings(const QString& scope, QObject* parent, QString& error);
+
+    class JSAPIExample : public QObject, public QScriptable {
+        Q_OBJECT
+        Q_PLUGIN_METADATA(IID "JSAPIExample" FILE "plugin.json")
+        Q_PROPERTY(QString version MEMBER _version CONSTANT)
+    public:
+        JSAPIExample() {
+            setObjectName(JSAPI_EXPORT_NAME);
+            auto scriptInit = DependencyManager::get<ScriptInitializers>();
+            if (!scriptInit) {
+                qCWarning(logger) << "COULD NOT INITIALIZE (ScriptInitializers unavailable)" << qApp << this;
+                return;
+            }
+            qCWarning(logger) << "registering w/ScriptInitializerMixin..." << scriptInit.data();
+            scriptInit->registerScriptInitializer([this](QScriptEngine* engine) {
+                auto value = engine->newQObject(this, QScriptEngine::QtOwnership, QScriptEngine::ExcludeDeleteLater);
+                engine->globalObject().setProperty(objectName(), value);
+                // qCDebug(logger) << "setGlobalInstance" << objectName() << engine->property("fileName");
+            });
+            // qCInfo(logger) << "plugin loaded" << qApp << toString() << QThread::currentThread();
+        }
+
+        // NOTES: everything within the "public slots:" section below will be available from JS via overall plugin QObject
+        //    also, to demonstrate future-proofing JS API code, QVariant's are used throughout most of these examples --
+        //    which still makes them very Qt-specific, but avoids depending directly on deprecated QtScript/QScriptValue APIs.
+        //    (as such this plugin class and its methods remain forward-compatible with other engines like QML's QJSEngine)
+
+    public slots:
+        // pretty-printed representation for logging eg: print(JSAPIExample)
+        // (note: Qt script engines automatically look for a ".toString" method on native classes when coercing values to strings)
+        QString toString() const { return QString("[%1 version=%2]").arg(objectName()).arg(_version); }
+
+        /**jsdoc
+         * Returns current microseconds (usecs) since Epoch. note: 1000usecs == 1ms
+         * @example <caption>Measure current setTimeout accuracy.</caption>
+         * var expected = 1000;
+         * var start = JSAPIExample.now();
+         * Script.setTimeout(function () {
+         *     var elapsed = (JSAPIExample.now() - start)/1000;
+         *     print("expected (ms):", expected, "actual (ms):", elapsed);
+         * }, expected);
+         */
+        QVariant now() const { return usecTimestampNow(); }
+
+        /**jsdoc
+         * Example of returning a JS Object key-value map
+         * @example <caption>"zip" a list of keys and corresponding values to form key-value map</caption>
+         * print(JSON.stringify(JSAPIExample.zip(["a","b"], [1,2])); // { "a": 1, "b": 2 }
+         */
+        QVariant zip(const QStringList& keys, const QVariantList& values) const {
+            QVariantMap out;
+            for (int i = 0; i < keys.size(); i++) {
+                out[keys[i]] = i < values.size() ? values[i] : QVariant();
+            }
+            return out;
+        }
+
+        /**jsdoc
+         * Example of returning a JS Array result
+         * @example <caption>emulate Object.values(keyValues)</caption>
+         * print(JSON.stringify(JSAPIExample.values({ "a": 1, "b": 2 }))); // [1,2]
+         */
+        QVariant values(const QVariantMap& keyValues) const {
+            QVariantList values = keyValues.values();
+            return values;
+        }
+
+        /**jsdoc
+         * Another example of returning JS Array data
+         * @example <caption>generate an integer sequence (inclusive of [from, to])</caption>
+         * print(JSON.stringify(JSAPIExample.seq(1,5)));// [1,2,3,4,5]
+         */
+        QVariant seq(int from, int to) const {
+            QVariantList out;
+            for (int i = from; i <= to; i++) {
+                out.append(i);
+            }
+            return out;
+        }
+
+        /**jsdoc
+         * Example of returning arbitrary binary data from C++ (resulting in a JS ArrayBuffer)
+         * see also: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer#Examples
+         * @example <caption>return compressed/decompressed versions of the input data</caption>
+         * var data = "testing 1 2 3";
+         * var z = JSAPIExample.qCompressString(data); // z will be an ArrayBuffer
+         * var u = JSAPIExample.qUncompressString(z); // u will be a String value
+         * print(JSON.stringify({ input: data, compressed: z.byteLength, output: u, uncompressed: u.length }));
+         */
+        QVariant qCompressString(const QString& jsString, int compress_level = -1) const {
+            QByteArray arrayBuffer = qCompress(jsString.toUtf8(), compress_level);
+            return arrayBuffer;
+        }
+        QVariant qUncompressString(const QByteArray& arrayBuffer) const {
+            QString jsString = QString::fromUtf8(qUncompress(arrayBuffer));
+            return jsString;
+        }
+
+        /**
+          * Example of exposing a custom "managed" C++ QObject to JS
+          * The lifecycle of the created QObject* instance becomes managed by the invoking QScriptEngine --
+          * it will be automatically cleaned up once no longer reachable from any JS variables/closures.
+          * @example <caption>access persistent settings stored in separate .json files</caption>
+          * var settings = JSAPIExample.getScopedSettings("example");
+          * print("example settings stored in:", settings.fileName());
+          * print("(before) example::timestamp", settings.getValue("timestamp"));
+          * settings.setValue("timestamp", Date.now());
+          * print("(after) example::timestamp", settings.getValue("timestamp"));
+          * print("all example::* keys", settings.allKeys());
+          * settings = null; // optional best pratice; allows the object to be reclaimed ASAP by the JS garbage collector
+          */
+        QScriptValue getScopedSettings(const QString& scope) {
+            auto engine = QScriptable::engine();
+            if (!engine) {
+                return QScriptValue::NullValue;
+            }
+            QString error;
+            auto cppValue = createScopedSettings(scope, engine, error);
+            if (!cppValue) {
+                raiseScriptingError(context(), "error creating scoped settings instance: " + error);
+                return QScriptValue::NullValue;
+            }
+            return engine->newQObject(cppValue, QScriptEngine::ScriptOwnership, QScriptEngine::ExcludeDeleteLater);
+        }
+
+    private:
+        const QString _version { JSAPI_SEMANTIC_VERSION };
+    };
+
+    // JSSettingsHelper wraps a scoped (prefixed/separate) QSettings and exposes a subset of QSetting APIs as slots
+    class JSSettingsHelper : public QObject {
+        Q_OBJECT
+    public:
+        JSSettingsHelper(const QString& scope, QObject* parent = nullptr);
+        ~JSSettingsHelper();
+        operator bool() const;
+    public slots:
+        QString fileName() const;
+        QString toString() const;
+        QVariant getValue(const QString& key, const QVariant& defaultValue = QVariant());
+        bool setValue(const QString& key, const QVariant& value);
+        QStringList allKeys() const;
+    protected:
+        QString _scope;
+        QString _fileName;
+        QSharedPointer<QSettings> _settings;
+        QString getLocalSettingsPath(const QString& scope) const;
+    };
+
+    // verifies the requested scope is sensible and creates/returns a scoped JSSettingsHelper instance
+    QObject* createScopedSettings(const QString& scope, QObject* parent, QString& error) {
+        const QRegExp VALID_SETTINGS_SCOPE { "[-_A-Za-z0-9]{1,64}" };
+        if (!VALID_SETTINGS_SCOPE.exactMatch(scope)) {
+            error = QString("invalid scope (expected alphanumeric <= 64 chars not '%1')").arg(scope);
+            return nullptr;
+        }
+        return new JSSettingsHelper(scope, parent);
+    }
+
+    // --------------------------------------------------
+    // ----- inline JSSettingsHelper implementation -----
+    JSSettingsHelper::operator bool() const {
+        return (bool)_settings;
+    }
+    JSSettingsHelper::JSSettingsHelper(const QString& scope, QObject* parent) :
+        QObject(parent), _scope(scope), _fileName(getLocalSettingsPath(scope)),
+        _settings(_fileName.isEmpty() ? nullptr : new QSettings(_fileName, JSON_FORMAT)) {
+    }
+    JSSettingsHelper::~JSSettingsHelper() {
+        qCDebug(logger) << "~JSSettingsHelper" << _scope << _fileName << this;
+    }
+    QString JSSettingsHelper::fileName() const {
+        return _settings ? _settings->fileName() : "";
+    }
+    QString JSSettingsHelper::toString() const {
+        return QString("[JSSettingsHelper scope=%1 valid=%2]").arg(_scope).arg((bool)_settings);
+    }
+    QVariant JSSettingsHelper::getValue(const QString& key, const QVariant& defaultValue) {
+        return _settings ? _settings->value(key, defaultValue) : defaultValue;
+    }
+    bool JSSettingsHelper::setValue(const QString& key, const QVariant& value) {
+        if (_settings) {
+            if (value.isValid()) {
+                _settings->setValue(key, value);
+            } else {
+                _settings->remove(key);
+            }
+            return true;
+        }
+        return false;
+    }
+    QStringList JSSettingsHelper::allKeys() const {
+        return _settings ? _settings->allKeys() : QStringList{};
+    }
+    QString JSSettingsHelper::getLocalSettingsPath(const QString& scope) const {
+        // generate a prefixed filename (relative to the main application's Interface.json file)
+        const QString fileName = QString("jsapi_%1.json").arg(scope);
+        return QFileInfo(::settingsFilename()).dir().filePath(fileName);
+    }
+    // ----- /inline JSSettingsHelper implementation -----
+
+}  // namespace REPLACE_ME_WITH_UNIQUE_NAME
+
+#include "JSAPIExample.moc"
diff --git a/plugins/JSAPIExample/src/plugin.json b/plugins/JSAPIExample/src/plugin.json
new file mode 100644
index 0000000000..f28c7fb988
--- /dev/null
+++ b/plugins/JSAPIExample/src/plugin.json
@@ -0,0 +1,4 @@
+{
+    "name":"JS API Example",
+    "version": 1
+}
diff --git a/plugins/KasenAPIExample/CMakeLists.txt b/plugins/KasenAPIExample/CMakeLists.txt
deleted file mode 100644
index 96ac84e10d..0000000000
--- a/plugins/KasenAPIExample/CMakeLists.txt
+++ /dev/null
@@ -1,3 +0,0 @@
-set(TARGET_NAME KasenAPIExample)
-setup_hifi_client_server_plugin(scripting)
-link_hifi_libraries(shared plugins avatars networking graphics gpu)
diff --git a/plugins/KasenAPIExample/src/ExampleScriptPlugin.h b/plugins/KasenAPIExample/src/ExampleScriptPlugin.h
deleted file mode 100644
index 76c0a494d7..0000000000
--- a/plugins/KasenAPIExample/src/ExampleScriptPlugin.h
+++ /dev/null
@@ -1,58 +0,0 @@
-//
-//  ExampleScriptPlugin.h
-//  plugins/KasenAPIExample/src
-//
-//  Created by Kasen IO on 2019.07.14 | realities.dev | kasenvr@gmail.com
-//  Copyright 2019 Kasen IO
-//
-//  Authored by: Humbletim (humbletim@gmail.com)
-//
-//  Distributed under the Apache License, Version 2.0.
-//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
-//
-//  Supporting file containing all QtScript specific integration.
-
-#ifndef EXAMPLE_SCRIPT_PLUGIN_H
-#define EXAMPLE_SCRIPT_PLUGIN_H
-
-#if DEV_BUILD
-#pragma message("QtScript is deprecated see: doc.qt.io/qt-5/topics-scripting.html")
-#endif
-#include <QtScript/QScriptEngine>
-
-#include <QtCore/QLoggingCategory>
-#include <QCoreApplication>
-#include <shared/ScriptInitializerMixin.h>
-
-namespace example {
-
-extern const QLoggingCategory& logger;
-
-inline void setGlobalInstance(QScriptEngine* engine, const QString& name, QObject* object) {
-    auto value = engine->newQObject(object, QScriptEngine::QtOwnership);
-    engine->globalObject().setProperty(name, value);
-    qCDebug(logger) << "setGlobalInstance" << name << engine->property("fileName");
-}
-
-class ScriptPlugin : public QObject {
-    Q_OBJECT
-    QString _version;
-    Q_PROPERTY(QString version MEMBER _version CONSTANT)
-protected:
-    inline ScriptPlugin(const QString& name, const QString& version) : _version(version) {
-        setObjectName(name);
-        if (!DependencyManager::get<ScriptInitializers>()) {
-            qCWarning(logger) << "COULD NOT INITIALIZE (ScriptInitializers unavailable)" << qApp << this;
-            return;
-        }
-        qCWarning(logger) << "registering w/ScriptInitializerMixin..." << DependencyManager::get<ScriptInitializers>().data();
-        DependencyManager::get<ScriptInitializers>()->registerScriptInitializer(
-            [this](QScriptEngine* engine) { setGlobalInstance(engine, objectName(), this); });
-    }
-public slots:
-    inline QString toString() const { return QString("[%1 version=%2]").arg(objectName()).arg(_version); }
-};
-
-}  // namespace example
-
-#endif
\ No newline at end of file
diff --git a/plugins/KasenAPIExample/src/KasenAPIExample.cpp b/plugins/KasenAPIExample/src/KasenAPIExample.cpp
deleted file mode 100644
index 720c47f6cd..0000000000
--- a/plugins/KasenAPIExample/src/KasenAPIExample.cpp
+++ /dev/null
@@ -1,141 +0,0 @@
-//
-//  KasenAPIExample.cpp
-//  plugins/KasenAPIExample/src
-//
-//  Created by Kasen IO on 2019.07.14 | realities.dev | kasenvr@gmail.com
-//  Copyright 2019 Kasen IO
-//
-//  Authored by: Humbletim (humbletim@gmail.com)
-//
-//  Distributed under the Apache License, Version 2.0.
-//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
-//
-//  Example of prototyping new JS APIs by leveraging the existing plugin system.
-
-#include "ExampleScriptPlugin.h"
-
-#include <QCoreApplication>
-#include <QtCore/QJsonObject>
-#include <QtCore/QLoggingCategory>
-#include <QtCore/QThread>
-#include <QtCore/QTimer>
-
-#include <SharedUtil.h>
-#include <AvatarHashMap.h>
-
-namespace custom_api_example {
-
-QLoggingCategory logger{ "custom_api_example" };
-
-class KasenAPIExample : public example::ScriptPlugin {
-    Q_OBJECT
-    Q_PLUGIN_METADATA(IID "KasenAPIExample" FILE "plugin.json")
-public:
-    KasenAPIExample() : example::ScriptPlugin("KasenAPIExample", "0.0.1") {
-        qCInfo(logger) << "plugin loaded" << qApp << toString() << QThread::currentThread(); 
-    }
-
-public slots:
-    /**jsdoc
-     * Returns current microseconds (usecs) since Epoch. note: 1000usecs == 1ms
-     * @example <caption>Measure current setTimeout accuracy.</caption>
-     * var expected = 1000;
-     * var start = KasenAPIExample.now();
-     * Script.setTimeout(function () {
-     *     var elapsed = (KasenAPIExample.now() - start)/1000;
-     *     print("expected (ms):", expected, "actual (ms):", elapsed);
-     * }, expected);
-     */
-    QVariant now() const {
-        return usecTimestampNow();
-    }
-
-    /**jsdoc
-     * Returns the available blendshape names for an avatar.
-     * @example <caption>Get blendshape names</caption>
-     * print(JSON.stringify(KasenAPIExample.getBlendshapeNames(MyAvatar.sessionUUID)));
-     */
-    QStringList getBlendshapeNames(const QUuid& avatarID) const {
-        QVector<QString> out;
-        if (auto head = getAvatarHead(avatarID)) {
-            for (const auto& kv : head->getBlendshapeMap().toStdMap()) {
-                if (kv.second >= out.size()) out.resize(kv.second+1);
-                out[kv.second] = kv.first;
-            }
-        }
-        return out.toList();
-    }
-
-    /**jsdoc
-     * Returns a key-value object with active (non-zero) blendshapes.
-     * eg: { JawOpen: 1.0, ... }
-     * @example <caption>Get active blendshape map</caption>
-     * print(JSON.stringify(KasenAPIExample.getActiveBlendshapes(MyAvatar.sessionUUID)));
-     */
-    QVariant getActiveBlendshapes(const QUuid& avatarID) const {
-        if (auto head = getAvatarHead(avatarID)) {
-            return head->toJson()["blendShapes"].toVariant();
-        }
-        return {};
-    }
-
-    QVariant getBlendshapeMapping(const QUuid& avatarID) const {
-        QVariantMap out;
-        if (auto head = getAvatarHead(avatarID)) {
-            for (const auto& kv : head->getBlendshapeMap().toStdMap()) {
-                out[kv.first] = kv.second;
-            }
-        }
-        return out;
-    }
-
-    QVariant getBlendshapes(const QUuid& avatarID) const {
-        QVariantMap result;
-        if (auto head = getAvatarHead(avatarID)) {
-            QStringList names = getBlendshapeNames(avatarID);
-            auto states = head->getBlendshapeStates();
-            result = {
-                { "base", zipNonZeroValues(names, states.base) },
-                { "summed", zipNonZeroValues(names, states.summed) },
-                { "transient", zipNonZeroValues(names, states.transient) },
-            };
-        }
-        return result;
-    }
-
-private:
-    static QVariantMap zipNonZeroValues(const QStringList& keys, const QVector<float>& values) {
-        QVariantMap out;
-        for (int i=1; i < values.size(); i++) {
-            if (fabs(values[i]) > 1.0e-6f) {
-                out[keys.value(i)] = values[i];
-            }
-        }
-        return out;
-    }
-    struct _HeadHelper : public HeadData {
-        QMap<QString,int> getBlendshapeMap() const {
-            return BLENDSHAPE_LOOKUP_MAP;
-        }
-        struct States { QVector<float> base, summed, transient; };
-        States getBlendshapeStates() const {
-            return {
-                _blendshapeCoefficients,
-                _summedBlendshapeCoefficients,
-                _transientBlendshapeCoefficients
-            };
-        }
-    };
-    static const _HeadHelper* getAvatarHead(const QUuid& avatarID) {
-        auto avatars = DependencyManager::get<AvatarHashMap>();
-        auto avatar = avatars ? avatars->getAvatarBySessionID(avatarID) : nullptr;
-        auto head = avatar ? avatar->getHeadData() : nullptr;
-        return reinterpret_cast<const _HeadHelper*>(head);
-    }
-};
-
-}
-
-const QLoggingCategory& example::logger{ custom_api_example::logger };
-
-#include "KasenAPIExample.moc"
diff --git a/plugins/KasenAPIExample/src/plugin.json b/plugins/KasenAPIExample/src/plugin.json
deleted file mode 100644
index 3e6931deec..0000000000
--- a/plugins/KasenAPIExample/src/plugin.json
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-    "name":"Kasen JS API Example",
-    "version": 1,
-    "package": {
-        "author": "Revofire",
-        "homepage": "www.realities.dev",
-        "version": "0.0.1",
-        "engines": {
-          "hifi-interface": ">= 0.83.0",
-          "hifi-assignment-client": ">= 0.83.0"
-        },
-        "config": {
-            "client": true,
-            "entity_client": true,
-            "entity_server": true,
-            "edit_filter": true,
-            "agent": true,
-            "avatar": true
-        }
-    }
-}
diff --git a/scripts/system/create/edit.js b/scripts/system/create/edit.js
index 69e2e94818..099cb94988 100644
--- a/scripts/system/create/edit.js
+++ b/scripts/system/create/edit.js
@@ -146,20 +146,23 @@ var DEFAULT_DIMENSIONS = {
 
 var DEFAULT_LIGHT_DIMENSIONS = Vec3.multiply(20, DEFAULT_DIMENSIONS);
 
+var SUBMENU_ENTITY_EDITOR_PREFERENCES = "Edit > Create Application - Preferences";
 var MENU_AUTO_FOCUS_ON_SELECT = "Auto Focus on Select";
 var MENU_EASE_ON_FOCUS = "Ease Orientation on Focus";
 var MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE = "Show Lights and Particle Systems in Create Mode";
 var MENU_SHOW_ZONES_IN_EDIT_MODE = "Show Zones in Create Mode";
-
 var MENU_CREATE_ENTITIES_GRABBABLE = "Create Entities As Grabbable (except Zones, Particles, and Lights)";
 var MENU_ALLOW_SELECTION_LARGE = "Allow Selecting of Large Models";
 var MENU_ALLOW_SELECTION_SMALL = "Allow Selecting of Small Models";
 var MENU_ALLOW_SELECTION_LIGHTS = "Allow Selecting of Lights";
+var MENU_ENTITY_LIST_DEFAULT_RADIUS = "Entity List Default Radius";
 
 var SETTING_AUTO_FOCUS_ON_SELECT = "autoFocusOnSelect";
 var SETTING_EASE_ON_FOCUS = "cameraEaseOnFocus";
 var SETTING_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE = "showLightsAndParticlesInEditMode";
 var SETTING_SHOW_ZONES_IN_EDIT_MODE = "showZonesInEditMode";
+var SETTING_EDITOR_COLUMNS_SETUP = "editorColumnsSetup";
+var SETTING_ENTITY_LIST_DEFAULT_RADIUS = "entityListDefaultRadius";
 
 var SETTING_EDIT_PREFIX = "Edit/";
 
@@ -267,8 +270,6 @@ function adjustPositionPerBoundingBox(position, direction, registration, dimensi
     return position;
 }
 
-var GRABBABLE_ENTITIES_MENU_CATEGORY = "Edit";
-
 // Handles any edit mode updates required when domains have switched
 function checkEditPermissionsAndUpdate() {
     if ((createButton === null) || (createButton === undefined)) {
@@ -878,7 +879,12 @@ var toolBar = (function () {
 
         addButton("importEntitiesButton", function() {
             Window.browseChanged.connect(onFileOpenChanged);
-            Window.browseAsync("Select Model to Import", "", "*.json");
+            Window.browseAsync("Select .json to Import", "", "*.json");
+        });
+
+        addButton("importEntitiesFromUrlButton", function() {
+            Window.promptTextChanged.connect(onPromptTextChanged);
+            Window.promptAsync("URL of a .json to import", "");
         });
 
         addButton("openAssetBrowserButton", function() {
@@ -1378,11 +1384,9 @@ Controller.mouseReleaseEvent.connect(mouseReleaseEvent);
 // In order for editVoxels and editModels to play nice together, they each check to see if a "delete" menu item already
 // exists. If it doesn't they add it. If it does they don't. They also only delete the menu item if they were the one that
 // added it.
-var modelMenuAddedDelete = false;
 var originalLightsArePickable = Entities.getLightsArePickable();
 
 function setupModelMenus() {
-    // adj our menuitems
     Menu.addMenuItem({
         menuName: "Edit",
         menuItemName: "Undo",
@@ -1396,118 +1400,69 @@ function setupModelMenus() {
         position: 1,
     });
 
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Entities",
-        isSeparator: true
-    });
-    if (!Menu.menuItemExists("Edit", "Delete")) {
-        Menu.addMenuItem({
-            menuName: "Edit",
-            menuItemName: "Delete",
-            shortcutKeyEvent: {
-                text: "delete"
-            },
-            afterItem: "Entities",
-        });
-        modelMenuAddedDelete = true;
-    }
+    Menu.addMenu(SUBMENU_ENTITY_EDITOR_PREFERENCES);
 
     Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Parent Entity to Last",
-        afterItem: "Entities"
-    });
-
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Unparent Entity",
-        afterItem: "Parent Entity to Last"
-    });
-
-    Menu.addMenuItem({
-        menuName: GRABBABLE_ENTITIES_MENU_CATEGORY,
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_CREATE_ENTITIES_GRABBABLE,
-        afterItem: "Unparent Entity",
+        position: 0,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_EDIT_PREFIX + MENU_CREATE_ENTITIES_GRABBABLE, false)
     });
-
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_ALLOW_SELECTION_LARGE,
         afterItem: MENU_CREATE_ENTITIES_GRABBABLE,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_EDIT_PREFIX + MENU_ALLOW_SELECTION_LARGE, true)
     });
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_ALLOW_SELECTION_SMALL,
         afterItem: MENU_ALLOW_SELECTION_LARGE,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_EDIT_PREFIX + MENU_ALLOW_SELECTION_SMALL, true)
     });
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_ALLOW_SELECTION_LIGHTS,
         afterItem: MENU_ALLOW_SELECTION_SMALL,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_EDIT_PREFIX + MENU_ALLOW_SELECTION_LIGHTS, false)
     });
     Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Select All Entities In Box",
-        afterItem: "Allow Selecting of Lights"
-    });
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Select All Entities Touching Box",
-        afterItem: "Select All Entities In Box"
-    });
-
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Export Entities",
-        afterItem: "Entities"
-    });
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Import Entities",
-        afterItem: "Export Entities"
-    });
-    Menu.addMenuItem({
-        menuName: "Edit",
-        menuItemName: "Import Entities from URL",
-        afterItem: "Import Entities"
-    });
-
-    Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_AUTO_FOCUS_ON_SELECT,
+        afterItem: MENU_ALLOW_SELECTION_LIGHTS,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_AUTO_FOCUS_ON_SELECT) === "true"
     });
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_EASE_ON_FOCUS,
         afterItem: MENU_AUTO_FOCUS_ON_SELECT,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_EASE_ON_FOCUS) === "true"
     });
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE,
         afterItem: MENU_EASE_ON_FOCUS,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE) !== "false"
     });
     Menu.addMenuItem({
-        menuName: "Edit",
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
         menuItemName: MENU_SHOW_ZONES_IN_EDIT_MODE,
         afterItem: MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE,
         isCheckable: true,
         isChecked: Settings.getValue(SETTING_SHOW_ZONES_IN_EDIT_MODE) !== "false"
     });
+    Menu.addMenuItem({
+        menuName: SUBMENU_ENTITY_EDITOR_PREFERENCES,
+        menuItemName: MENU_ENTITY_LIST_DEFAULT_RADIUS,
+        afterItem: MENU_SHOW_ZONES_IN_EDIT_MODE
+    });
 
     Entities.setLightsArePickable(false);
 }
@@ -1518,29 +1473,16 @@ function cleanupModelMenus() {
     Menu.removeMenuItem("Edit", "Undo");
     Menu.removeMenuItem("Edit", "Redo");
 
-    Menu.removeSeparator("Edit", "Entities");
-    if (modelMenuAddedDelete) {
-        // delete our menuitems
-        Menu.removeMenuItem("Edit", "Delete");
-    }
-
-    Menu.removeMenuItem("Edit", "Parent Entity to Last");
-    Menu.removeMenuItem("Edit", "Unparent Entity");
-    Menu.removeMenuItem("Edit", "Allow Selecting of Large Models");
-    Menu.removeMenuItem("Edit", "Allow Selecting of Small Models");
-    Menu.removeMenuItem("Edit", "Allow Selecting of Lights");
-    Menu.removeMenuItem("Edit", "Select All Entities In Box");
-    Menu.removeMenuItem("Edit", "Select All Entities Touching Box");
-
-    Menu.removeMenuItem("Edit", "Export Entities");
-    Menu.removeMenuItem("Edit", "Import Entities");
-    Menu.removeMenuItem("Edit", "Import Entities from URL");
-
-    Menu.removeMenuItem("Edit", MENU_AUTO_FOCUS_ON_SELECT);
-    Menu.removeMenuItem("Edit", MENU_EASE_ON_FOCUS);
-    Menu.removeMenuItem("Edit", MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE);
-    Menu.removeMenuItem("Edit", MENU_SHOW_ZONES_IN_EDIT_MODE);
-    Menu.removeMenuItem("Edit", MENU_CREATE_ENTITIES_GRABBABLE);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_ALLOW_SELECTION_LARGE);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_ALLOW_SELECTION_SMALL);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_ALLOW_SELECTION_LIGHTS);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_AUTO_FOCUS_ON_SELECT);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_EASE_ON_FOCUS);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_SHOW_ZONES_IN_EDIT_MODE);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_CREATE_ENTITIES_GRABBABLE);
+    Menu.removeMenuItem(SUBMENU_ENTITY_EDITOR_PREFERENCES, MENU_ENTITY_LIST_DEFAULT_RADIUS);
+    Menu.removeMenu(SUBMENU_ENTITY_EDITOR_PREFERENCES);   
 }
 
 Script.scriptEnding.connect(function () {
@@ -1881,48 +1823,39 @@ function onPromptTextChanged(prompt) {
     }
 }
 
+function onPromptTextChangedDefaultRadiusUserPref(prompt) {
+    Window.promptTextChanged.disconnect(onPromptTextChangedDefaultRadiusUserPref);
+    if (prompt !== "") {
+        var radius = parseInt(prompt);
+        if (radius < 0 || isNaN(radius)){
+            radius = 100;
+        }
+        Settings.setValue(SETTING_ENTITY_LIST_DEFAULT_RADIUS, radius);
+    }
+}
+
 function handleMenuEvent(menuItem) {
-    if (menuItem === "Allow Selecting of Small Models") {
-        allowSmallModels = Menu.isOptionChecked("Allow Selecting of Small Models");
-    } else if (menuItem === "Allow Selecting of Large Models") {
-        allowLargeModels = Menu.isOptionChecked("Allow Selecting of Large Models");
-    } else if (menuItem === "Allow Selecting of Lights") {
-        Entities.setLightsArePickable(Menu.isOptionChecked("Allow Selecting of Lights"));
+    if (menuItem === MENU_ALLOW_SELECTION_SMALL) {
+        allowSmallModels = Menu.isOptionChecked(MENU_ALLOW_SELECTION_SMALL);
+    } else if (menuItem === MENU_ALLOW_SELECTION_LARGE) {
+        allowLargeModels = Menu.isOptionChecked(MENU_ALLOW_SELECTION_LARGE);
+    } else if (menuItem === MENU_ALLOW_SELECTION_LIGHTS) {
+        Entities.setLightsArePickable(Menu.isOptionChecked(MENU_ALLOW_SELECTION_LIGHTS));
     } else if (menuItem === "Delete") {
         deleteSelectedEntities();
     } else if (menuItem === "Undo") {
         undoHistory.undo();
     } else if (menuItem === "Redo") {
         undoHistory.redo();
-    } else if (menuItem === "Parent Entity to Last") {
-        parentSelectedEntities();
-    } else if (menuItem === "Unparent Entity") {
-        unparentSelectedEntities();
-    } else if (menuItem === "Export Entities") {
-        if (!selectionManager.hasSelection()) {
-            Window.notifyEditError("No entities have been selected.");
-        } else {
-            Window.saveFileChanged.connect(onFileSaveChanged);
-            Window.saveAsync("Select Where to Save", "", "*.json");
-        }
-    } else if (menuItem === "Import Entities" || menuItem === "Import Entities from URL") {
-        if (menuItem === "Import Entities") {
-            Window.browseChanged.connect(onFileOpenChanged);
-            Window.browseAsync("Select Model to Import", "", "*.json");
-        } else {
-            Window.promptTextChanged.connect(onPromptTextChanged);
-            Window.promptAsync("URL of SVO to import", "");
-        }
-    } else if (menuItem === "Select All Entities In Box") {
-        selectAllEntitiesInCurrentSelectionBox(false);
-    } else if (menuItem === "Select All Entities Touching Box") {
-        selectAllEntitiesInCurrentSelectionBox(true);
     } else if (menuItem === MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE) {
         entityIconOverlayManager.setVisible(isActive && Menu.isOptionChecked(MENU_SHOW_LIGHTS_AND_PARTICLES_IN_EDIT_MODE));
     } else if (menuItem === MENU_SHOW_ZONES_IN_EDIT_MODE) {
         Entities.setDrawZoneBoundaries(isActive && Menu.isOptionChecked(MENU_SHOW_ZONES_IN_EDIT_MODE));
     } else if (menuItem === MENU_CREATE_ENTITIES_GRABBABLE) {
         Settings.setValue(SETTING_EDIT_PREFIX + menuItem, Menu.isOptionChecked(menuItem));
+    } else if (menuItem === MENU_ENTITY_LIST_DEFAULT_RADIUS) {
+        Window.promptTextChanged.connect(onPromptTextChangedDefaultRadiusUserPref);
+        Window.promptAsync("Entity List Default Radius (in meters)", "" + Settings.getValue(SETTING_ENTITY_LIST_DEFAULT_RADIUS, 100));         
     }
     tooltip.show(false);
 }
diff --git a/scripts/system/create/entityList/entityList.js b/scripts/system/create/entityList/entityList.js
index 252481d44d..58cf4ce892 100644
--- a/scripts/system/create/entityList/entityList.js
+++ b/scripts/system/create/entityList/entityList.js
@@ -371,6 +371,16 @@ EntityListTool = function(shouldUseEditTabletApp) {
             SelectionManager.teleportToEntity();
         } else if (data.type === 'moveEntitySelectionToAvatar') {
             SelectionManager.moveEntitiesSelectionToAvatar();
+        } else if (data.type === 'loadConfigSetting') {
+            var columnsData = Settings.getValue(SETTING_EDITOR_COLUMNS_SETUP, "NO_DATA");
+            var defaultRadius = Settings.getValue(SETTING_ENTITY_LIST_DEFAULT_RADIUS, 100);
+            emitJSONScriptEvent({
+                "type": "loadedConfigSetting",
+                "columnsData": columnsData,
+                "defaultRadius": defaultRadius
+            });
+        } else if (data.type === 'saveColumnsConfigSetting') {
+            Settings.setValue(SETTING_EDITOR_COLUMNS_SETUP, data.columnsData);
         }
     };
 
diff --git a/scripts/system/create/entityList/html/entityList.html b/scripts/system/create/entityList/html/entityList.html
index b22cd87a65..a5f27bd3a8 100644
--- a/scripts/system/create/entityList/html/entityList.html
+++ b/scripts/system/create/entityList/html/entityList.html
@@ -154,7 +154,7 @@
                     <div class = "menu-item-caption">Move Selected Entities to Avatar</div>
                     <div class = "menu-item-shortcut"></div>
                 </div>
-            </button>            
+            </button>
         </div>
         <div class="entity-list-menu" id="selection-menu" >
             <button class="menu-button" id="selectall" >
@@ -209,23 +209,23 @@
             </button>
             <button class="menu-button" id="selectfamily" >
                 <div class = "menu-item">
-                    <div class = "menu-item-caption">Select Family</div>
+                    <div class = "menu-item-caption">Select Parent And All Its Children</div>
                     <div class = "menu-item-shortcut"></div>
                 </div>
             </button>
             <button class="menu-button" id="selecttopfamily" >
                 <div class = "menu-item">
-                    <div class = "menu-item-caption">Select Top Family</div>
+                    <div class = "menu-item-caption">Select Top Parent And All Its Children</div>
                     <div class = "menu-item-shortcut"></div>
                 </div>
-            </button>            
+            </button>
             <div class="menu-separator"></div>
             <button class="menu-button" id="teleport-to-entity" >
                 <div class = "menu-item">
                     <div class = "menu-item-caption">Teleport To Selected Entities</div>
                     <div class = "menu-item-shortcut"></div>
                 </div>
-            </button>      
+            </button>
         </div>
         <div id="menuBackgroundOverlay" ></div>
     </body>
diff --git a/scripts/system/create/entityList/html/js/entityList.js b/scripts/system/create/entityList/html/js/entityList.js
index be79593511..89eac5fb2f 100644
--- a/scripts/system/create/entityList/html/js/entityList.js
+++ b/scripts/system/create/entityList/html/js/entityList.js
@@ -20,7 +20,7 @@ const EMPTY_ENTITY_ID = "0";
 const MAX_LENGTH_RADIUS = 9;
 const MINIMUM_COLUMN_WIDTH = 24;
 const SCROLLBAR_WIDTH = 20;
-const RESIZER_WIDTH = 10;
+const RESIZER_WIDTH = 13; //Must be the number of COLUMNS - 1.
 const DELTA_X_MOVE_COLUMNS_THRESHOLD = 2;
 const DELTA_X_COLUMN_SWAP_POSITION = 5;
 const CERTIFIED_PLACEHOLDER = "** Certified **";
@@ -188,6 +188,8 @@ let selectedEntities = [];
 let entityList = null; // The ListView
 
 let hmdMultiSelectMode = false; 
+
+let lastSelectedEntity;
 /**
  * @type EntityListContextMenu
  */
@@ -283,6 +285,9 @@ const PROFILE = !ENABLE_PROFILING ? PROFILE_NOOP : function(name, fn, args) {
 
 function loaded() {    
     openEventBridge(function() {
+
+        var isColumnsSettingLoaded = false;
+        
         elEntityTable = document.getElementById("entity-table");
         elEntityTableHeader = document.getElementById("entity-table-header");
         elEntityTableBody = document.getElementById("entity-table-body");
@@ -331,7 +336,7 @@ function loaded() {
         elColumnsMultiselectBox = document.getElementById("entity-table-columns-multiselect-box");
         elColumnsOptions = document.getElementById("entity-table-columns-options");
         elToggleSpaceMode = document.getElementById('toggle-space-mode');
-        
+
         document.body.onclick = onBodyClick;
         elToggleLocked.onclick = function() {
             EventBridge.emitWebEvent(JSON.stringify({ type: 'toggleLocked' }));
@@ -618,9 +623,9 @@ function loaded() {
             
             ++columnIndex;
         }
-        
+
         elEntityTableHeaderRow = document.querySelectorAll("#entity-table thead th");
-        
+
         entityList = new ListView(elEntityTableBody, elEntityTableScroll, elEntityTableHeaderRow, createRow, updateRow,
                                   clearRow, preRefresh, postRefresh, preRefresh, WINDOW_NONVARIABLE_HEIGHT);
 
@@ -765,10 +770,10 @@ function loaded() {
                 let selectedIndex = selectedEntities.indexOf(entityID);
                 if (selectedIndex >= 0) {
                     selection = [];
-                    selection = selection.concat(selectedEntities);
+                    selection = selectedEntities.concat(selection);
                     selection.splice(selectedIndex, 1);
                 } else {
-                    selection = selection.concat(selectedEntities);
+                    selection = selectedEntities.concat(selection);
                 }
             } else if (clickEvent.shiftKey && selectedEntities.length > 0) {
                 let previousItemFound = -1;
@@ -1044,6 +1049,8 @@ function loaded() {
         function updateSelectedEntities(selectedIDs, autoScroll) {
             let notFound = false;
 
+            lastSelectedEntity = selectedIDs[selectedIDs.length - 1];
+
             // reset all currently selected entities and their rows first
             selectedEntities.forEach(function(id) {
                 let entity = entitiesByID[id];
@@ -1063,7 +1070,11 @@ function loaded() {
                 if (entity !== undefined) {
                     entity.selected = true;
                     if (entity.elRow) {
-                        entity.elRow.className = 'selected';
+                        if (id === lastSelectedEntity) {
+                            entity.elRow.className = 'last-selected';
+                        } else {
+                            entity.elRow.className = 'selected';
+                        }
                     }
                 } else {
                     notFound = true;
@@ -1132,7 +1143,11 @@ function loaded() {
 
             // if this entity was previously selected flag it's row as selected
             if (itemData.selected) {
-                elRow.className = 'selected';
+                if (itemData.id === lastSelectedEntity) {
+                    elRow.className = 'last-selected';
+                } else {
+                    elRow.className = 'selected';
+                }
             } else {
                 elRow.className = '';
             }
@@ -1409,6 +1424,10 @@ function loaded() {
                 column.elResizer.style.visibility = columnVisible && visibleColumns > 0 ? "visible" : "hidden";
             }
             
+            if (isColumnsSettingLoaded) {
+                EventBridge.emitWebEvent(JSON.stringify({ type: 'saveColumnsConfigSetting', columnsData: columns }));
+            }
+            
             entityList.refresh();
         }
         
@@ -1660,14 +1679,63 @@ function loaded() {
                     } else {
                         document.getElementById("hmdmultiselect").style.display = "none";                      
                     }
+                } else if (data.type === "loadedConfigSetting") {
+                    if (typeof(data.defaultRadius) === "number") {
+                        elFilterRadius.value = data.defaultRadius;
+                        onRadiusChange();
+                    }
+                    if (data.columnsData !== "NO_DATA" && typeof(data.columnsData) === "object") {
+                        var isValid = true;
+                        var originalColumnIDs = [];
+                        for (let originalColumnID in COLUMNS) {
+                            originalColumnIDs.push(originalColumnID);
+                        }                        
+                        for (let columnSetupIndex in data.columnsData) {
+                            var checkPresence = originalColumnIDs.indexOf(data.columnsData[columnSetupIndex].columnID);
+                            if (checkPresence === -1) {
+                                isValid = false;
+                                break;
+                            }
+                        }
+                        if (isValid) {
+                            for (var columnIndex = 0; columnIndex < data.columnsData.length; columnIndex++) {
+                                if (data.columnsData[columnIndex].data.alwaysShown !== true) {
+                                    var columnDropdownID = "entity-table-column-" + data.columnsData[columnIndex].columnID;
+                                    if (data.columnsData[columnIndex].width !== 0) {
+                                        document.getElementById(columnDropdownID).checked = false;
+                                        document.getElementById(columnDropdownID).click();
+                                    } else {
+                                        document.getElementById(columnDropdownID).checked = true;
+                                        document.getElementById(columnDropdownID).click();
+                                    }
+                                }
+                            }
+                            for (columnIndex = 0; columnIndex < data.columnsData.length; columnIndex++) {
+                                let currentColumnIndex = originalColumnIDs.indexOf(data.columnsData[columnIndex].columnID);
+                                if (currentColumnIndex !== -1 && columnIndex !== currentColumnIndex) {
+                                    for (var i = currentColumnIndex; i > columnIndex; i--) {
+                                        swapColumns(i - 1, i);
+                                        var swappedContent = originalColumnIDs[i - 1];  
+                                        originalColumnIDs[i - 1] = originalColumnIDs[i];  
+                                        originalColumnIDs[i] = swappedContent;                                        
+                                    }
+                                }
+                            }
+                        } else {
+                            EventBridge.emitWebEvent(JSON.stringify({ type: 'saveColumnsConfigSetting', columnsData: "" }));
+                        }
+                    }
+                    isColumnsSettingLoaded = true;
                 }
             });
         }
-        
+
         refreshSortOrder();
         refreshEntities();
         
         window.addEventListener("resize", updateColumnWidths);
+        
+        EventBridge.emitWebEvent(JSON.stringify({ type: 'loadConfigSetting' }));
     });
     
     augmentSpinButtons();
@@ -1683,6 +1751,7 @@ function loaded() {
     // close context menu when switching focus to another window
     $(window).blur(function() {
         entityListContextMenu.close();
+        closeAllEntityListMenu();
     });
     
     function closeAllEntityListMenu() {
diff --git a/scripts/system/create/entitySelectionTool/entitySelectionTool.js b/scripts/system/create/entitySelectionTool/entitySelectionTool.js
index ffa828affe..71edbde765 100644
--- a/scripts/system/create/entitySelectionTool/entitySelectionTool.js
+++ b/scripts/system/create/entitySelectionTool/entitySelectionTool.js
@@ -668,6 +668,7 @@ SelectionManager = (function() {
                 var newPosition = Vec3.sum(relativePosition, targetPosition);
                 Entities.editEntity(id, { "position": newPosition });
             }
+            pushCommandForSelections();
             that._update(false, this);
         } else {
             audioFeedback.rejection();
@@ -797,6 +798,7 @@ SelectionDisplay = (function() {
     const COLOR_ROTATE_CURRENT_RING = { red: 255, green: 99, blue: 9 };
     const COLOR_BOUNDING_EDGE = { red: 160, green: 160, blue: 160 };
     const COLOR_BOUNDING_EDGE_PARENT = { red: 194, green: 123, blue: 0 };
+    const COLOR_BOUNDING_EDGE_PARENT_AND_CHILDREN = { red: 179, green: 0, blue: 134 };
     const COLOR_BOUNDING_EDGE_CHILDREN = { red: 0, green: 168, blue: 214 };
     const COLOR_SCALE_CUBE = { red: 192, green: 192, blue: 192 };
     const COLOR_DEBUG_PICK_PLANE = { red: 255, green: 255, blue: 255 };
@@ -1933,10 +1935,10 @@ SelectionDisplay = (function() {
                 var parentState = getParentState(SelectionManager.selections[0]);
                 if (parentState === "CHILDREN") {
                     handleBoundingBoxColor = COLOR_BOUNDING_EDGE_CHILDREN;
-                } else {
-                    if (parentState === "PARENT" || parentState === "PARENT_CHILDREN") {
-                        handleBoundingBoxColor = COLOR_BOUNDING_EDGE_PARENT;
-                    }
+                } else if (parentState === "PARENT") {
+                    handleBoundingBoxColor = COLOR_BOUNDING_EDGE_PARENT;
+                } else if (parentState === "PARENT_CHILDREN") {
+                    handleBoundingBoxColor = COLOR_BOUNDING_EDGE_PARENT_AND_CHILDREN;
                 }
             }
             
diff --git a/scripts/system/create/qml/EditTabView.qml b/scripts/system/create/qml/EditTabView.qml
index 53f6068424..617cdd9e5a 100644
--- a/scripts/system/create/qml/EditTabView.qml
+++ b/scripts/system/create/qml/EditTabView.qml
@@ -201,11 +201,11 @@ TabBar {
 
                     HifiControls.Button {
                         id: importButton
-                        text: "Import Entities (.json)"
+                        text: "Import Entities (.json) from a File"
                         color: hifi.buttons.black
                         colorScheme: hifi.colorSchemes.dark
-                        anchors.right: parent.right
-                        anchors.rightMargin: 30
+                        anchors.right: parent.horizontalCenter
+                        anchors.rightMargin: 10
                         anchors.left: parent.left
                         anchors.leftMargin: 30
                         anchors.top: assetServerButton.bottom
@@ -217,6 +217,25 @@ TabBar {
                             });
                         }
                     }
+                    
+                    HifiControls.Button {
+                        id: importButtonFromUrl
+                        text: "Import Entities (.json) from a URL"
+                        color: hifi.buttons.black
+                        colorScheme: hifi.colorSchemes.dark
+                        anchors.right: parent.right
+                        anchors.rightMargin: 30
+                        anchors.left: parent.horizontalCenter
+                        anchors.leftMargin: 10
+                        anchors.top: assetServerButton.bottom
+                        anchors.topMargin: 20
+                        onClicked: {
+                            editRoot.sendToScript({
+                                method: "newEntityButtonClicked",
+                                params: { buttonName: "importEntitiesFromUrlButton" }
+                            });
+                        }
+                    }
                 }
             } // Flickable
         }
diff --git a/scripts/system/create/qml/EditToolsTabView.qml b/scripts/system/create/qml/EditToolsTabView.qml
index 0ce8d8e8d4..2403604342 100644
--- a/scripts/system/create/qml/EditToolsTabView.qml
+++ b/scripts/system/create/qml/EditToolsTabView.qml
@@ -207,11 +207,11 @@ TabBar {
 
                     HifiControls.Button {
                         id: importButton
-                        text: "Import Entities (.json)"
+                        text: "Import Entities (.json) from a File"
                         color: hifi.buttons.black
                         colorScheme: hifi.colorSchemes.dark
-                        anchors.right: parent.right
-                        anchors.rightMargin: 55
+                        anchors.right: parent.horizontalCenter
+                        anchors.rightMargin: 10
                         anchors.left: parent.left
                         anchors.leftMargin: 55
                         anchors.top: assetServerButton.bottom
@@ -223,6 +223,25 @@ TabBar {
                             });
                         }
                     }
+
+                    HifiControls.Button {
+                        id: importButtonFromUrl
+                        text: "Import Entities (.json) from a URL"
+                        color: hifi.buttons.black
+                        colorScheme: hifi.colorSchemes.dark
+                        anchors.right: parent.right
+                        anchors.rightMargin: 55
+                        anchors.left: parent.horizontalCenter
+                        anchors.leftMargin: 10
+                        anchors.top: assetServerButton.bottom
+                        anchors.topMargin: 20
+                        onClicked: {
+                            editRoot.sendToScript({
+                                method: "newEntityButtonClicked",
+                                params: { buttonName: "importEntitiesFromUrlButton" }
+                            });
+                        }
+                    }
                 }
             } // Flickable
         }
diff --git a/scripts/system/html/css/edit-style.css b/scripts/system/html/css/edit-style.css
index 1f1fb9c86a..4f0a833a13 100644
--- a/scripts/system/html/css/edit-style.css
+++ b/scripts/system/html/css/edit-style.css
@@ -109,7 +109,6 @@ table {
 thead {
     font-family: Raleway-Regular;
     font-size: 12px;
-    text-transform: uppercase;
     background-color: #1c1c1c;
     padding: 1px 0;
     border-bottom: 1px solid #575757;
@@ -184,6 +183,15 @@ tr.selected + tr.selected {
     border-top: 1px solid #2e2e2e;
 }
 
+tr.last-selected {
+    color: #000000;
+    background-color: #0064ef;
+}
+
+tr.last-selected + tr.last-selected {
+    border-top: 1px solid #2e2e2e;
+}
+
 th {
     text-align: center;
     word-wrap: nowrap;
diff --git a/tools/ci-scripts/upload.py b/tools/ci-scripts/upload.py
index f43fbfd574..ab96e4ba24 100644
--- a/tools/ci-scripts/upload.py
+++ b/tools/ci-scripts/upload.py
@@ -6,19 +6,18 @@ import boto3
 import glob
 from github import Github
 
-
 def main():
-    bucket_name = os.environ['BUCKET_NAME']
+    bucket_name = os.environ['UPLOAD_BUCKET']
     upload_prefix = os.environ['UPLOAD_PREFIX']
     release_number = os.environ['RELEASE_NUMBER']
-    full_prefix = upload_prefix + '/' + release_number[0:-2] + '/' + release_number
+    full_prefix = upload_prefix + '/' + release_number
     S3 = boto3.client('s3')
     path = os.path.join(os.getcwd(), os.environ['ARTIFACT_PATTERN'])
     files = glob.glob(path, recursive=False)
     for archiveFile in files:
         filePath, fileName = os.path.split(archiveFile)
         S3.upload_file(os.path.join(filePath, fileName), bucket_name, full_prefix + '/' + fileName)
-        print("Uploaded Artifact to S3: https://{}.s3-us-west-2.amazonaws.com/{}/{}".format(bucket_name, full_prefix, fileName))
+        print("Uploaded Artifact to S3: https://{}.s3-eu-west-3.amazonaws.com/{}/{}".format(bucket_name, full_prefix, fileName))
     print("Finished")
 
 main()