diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 21e4db42a..db306b4d6 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -3,7 +3,9 @@
 
 name: Node.js CI
 
-on: [pull_request]
+on:
+  pull_request:
+  workflow_call:
 
 permissions:
   contents: read
diff --git a/.github/workflows/keyboard_plugin_test.yml b/.github/workflows/keyboard_plugin_test.yml
deleted file mode 100644
index e64efe983..000000000
--- a/.github/workflows/keyboard_plugin_test.yml
+++ /dev/null
@@ -1,66 +0,0 @@
-# Workflow for running the keyboard navigation plugin's automated tests.
-
-name: Keyboard Navigation Automated Tests
-
-on:
-  workflow_dispatch:
-  pull_request:
-  push:
-    branches:
-      - main
-
-permissions:
-  contents: read
-
-jobs:
-  webdriverio_tests:
-    name: WebdriverIO tests
-    timeout-minutes: 10
-    runs-on: ${{ matrix.os }}
-
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-latest]
-
-    steps:
-      - name: Checkout core Blockly
-        uses: actions/checkout@v5
-        with:
-          path: core-blockly
-
-      - name: Checkout keyboard navigation plugin
-        uses: actions/checkout@v5
-        with:
-          repository: 'google/blockly-keyboard-experimentation'
-          ref: 'main'
-          path: blockly-keyboard-experimentation
-
-      - name: Use Node.js 20.x
-        uses: actions/setup-node@v5
-        with:
-          node-version: 20.x
-
-      - name: NPM install
-        run: |
-          cd core-blockly
-          npm install
-          cd ..
-          cd blockly-keyboard-experimentation
-          npm install
-          cd ..
-
-      - name: Link latest core main with plugin
-        run: |
-          cd core-blockly/packages/blockly
-          npm run package
-          cd dist
-          npm link
-          cd ../../../../blockly-keyboard-experimentation
-          npm link blockly
-          cd ..
-
-      - name: Run keyboard navigation plugin tests
-        run: |
-          cd blockly-keyboard-experimentation
-          npm run test
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 000000000..0f403f447
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,137 @@
+name: Publish to npm
+
+on:
+  workflow_dispatch:
+    inputs:
+      dry_run:
+        description: 'Dry run - print the version that would be published, but do not commit or publish anything.'
+        required: false
+        default: false
+        type: boolean
+      skip_versioning:
+        description: >
+          Skip version bump - use the version already in the repo
+          (e.g. retry after npm publish failed but the release commit is already pushed).
+        required: false
+        default: false
+        type: boolean
+
+permissions:
+  contents: write
+  id-token: write
+
+jobs:
+  ci:
+    uses: ./.github/workflows/build.yml
+
+  version:
+    needs: ci
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    outputs:
+      version: ${{ steps.version.outputs.version }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 0
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v5
+        with:
+          node-version: 24.x
+          registry-url: 'https://registry.npmjs.org'
+
+      - name: Install dependencies
+        if: ${{ !inputs.skip_versioning }}
+        run: npm ci
+
+      - name: Determine version bump
+        id: bump
+        if: ${{ !inputs.skip_versioning }}
+        working-directory: packages/blockly
+        run: |
+          RELEASE_TYPE=$(npx conventional-recommended-bump --preset conventionalcommits -t blockly-)
+          echo "release_type=$RELEASE_TYPE" >> "$GITHUB_OUTPUT"
+          echo "Recommended bump: $RELEASE_TYPE"
+
+      - name: Apply version bump
+        if: ${{ !inputs.skip_versioning }}
+        working-directory: packages/blockly
+        run: npm version ${{ steps.bump.outputs.release_type }} --no-git-tag-version
+
+      - name: Read package version
+        id: version
+        working-directory: packages/blockly
+        run: |
+          VERSION=$(node -p "require('./package.json').version")
+          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
+          echo "Version: $VERSION"
+
+      - name: Upload versioned files
+        if: ${{ !inputs.skip_versioning }}
+        uses: actions/upload-artifact@v4
+        with:
+          name: versioned-files
+          path: |
+            packages/blockly/package.json
+            package-lock.json
+
+  publish:
+    needs: version
+    runs-on: ubuntu-latest
+    if: ${{ !inputs.dry_run }}
+    environment: release
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 0
+          ssh-key: ${{ secrets.DEPLOY_PRIVATE_KEY }}
+
+      - name: Download versioned files
+        if: ${{ !inputs.skip_versioning }}
+        uses: actions/download-artifact@v4
+        with:
+          name: versioned-files
+
+      - name: Commit and push version bump
+        if: ${{ !inputs.skip_versioning }}
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git add packages/blockly/package.json package-lock.json
+          git commit -m "release: v${{ needs.version.outputs.version }}"
+          git push
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v5
+        with:
+          node-version: 24.x
+          registry-url: 'https://registry.npmjs.org'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build package
+        working-directory: packages/blockly
+        run: npm run package
+
+      - name: Publish to npm
+        working-directory: packages/blockly/dist
+        run: npm publish --verbose
+
+      - name: Create tarball
+        working-directory: packages/blockly
+        run: npm pack ./dist
+
+      - name: Create GitHub release
+        working-directory: packages/blockly
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          TARBALL="blockly-${{ needs.version.outputs.version }}.tgz"
+          gh release create "blockly-v${{ needs.version.outputs.version }}" "$TARBALL" \
+            --repo "$GITHUB_REPOSITORY" \
+            --title "blockly-v${{ needs.version.outputs.version }}" \
+            --generate-notes
diff --git a/.github/workflows/update-gh-pages.yml b/.github/workflows/update-gh-pages.yml
new file mode 100644
index 000000000..e45aca688
--- /dev/null
+++ b/.github/workflows/update-gh-pages.yml
@@ -0,0 +1,36 @@
+# Manual workflow to update GitHub Pages from a chosen source branch.
+# The gulp updateGithubPages task builds the repo and force-pushes to gh-pages.
+
+name: Update GitHub Pages
+
+on:
+  workflow_dispatch:
+    inputs:
+      source_branch:
+        description: 'Source branch to build and deploy to GitHub Pages'
+        required: true
+        type: string
+        default: main
+
+permissions:
+  contents: write
+
+jobs:
+  update-gh-pages:
+    timeout-minutes: 15
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+        with:
+          ref: ${{ inputs.source_branch }}
+          fetch-depth: 0
+
+      - name: Use Node.js
+        uses: actions/setup-node@v5
+        with:
+          node-version: 24.x
+
+      - name: Update GitHub Pages
+        working-directory: ./packages/blockly
+        run: npm run updateGithubPages:staging
diff --git a/package-lock.json b/package-lock.json
index a02898fb6..0a4f05b47 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -18,15 +18,11 @@
     },
     "node_modules/@acemir/cssom": {
       "version": "0.9.31",
-      "resolved": "https://registry.npmjs.org/@acemir/cssom/-/cssom-0.9.31.tgz",
-      "integrity": "sha512-ZnR3GSaH+/vJ0YlHau21FjfLYjMpYVIzTD8M8vIEQvIGxeOXyXdzCI140rrCY862p/C/BbzWsjc1dgnM9mkoTA==",
       "dev": true,
       "license": "MIT"
     },
     "node_modules/@asamuzakjp/css-color": {
       "version": "4.1.2",
-      "resolved": "https://registry.npmjs.org/@asamuzakjp/css-color/-/css-color-4.1.2.tgz",
-      "integrity": "sha512-NfBUvBaYgKIuq6E/RBLY1m0IohzNHAYyaJGuTK79Z23uNwmz2jl1mPsC5ZxCCxylinKhT1Amn5oNTlx1wN8cQg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -39,8 +35,6 @@
     },
     "node_modules/@asamuzakjp/css-color/node_modules/lru-cache": {
       "version": "11.2.7",
-      "resolved": "https://registry.npmjs.org/lru-cache/-/lru-cache-11.2.7.tgz",
-      "integrity": "sha512-aY/R+aEsRelme17KGQa/1ZSIpLpNYYrhcrepKTZgE+W3WM16YMCaPwOHLHsmopZHELU0Ojin1lPVxKR0MihncA==",
       "dev": true,
       "license": "BlueOak-1.0.0",
       "engines": {
@@ -49,8 +43,6 @@
     },
     "node_modules/@asamuzakjp/dom-selector": {
       "version": "6.8.1",
-      "resolved": "https://registry.npmjs.org/@asamuzakjp/dom-selector/-/dom-selector-6.8.1.tgz",
-      "integrity": "sha512-MvRz1nCqW0fsy8Qz4dnLIvhOlMzqDVBabZx6lH+YywFDdjXhMY37SmpV1XFX3JzG5GWHn63j6HX6QPr3lZXHvQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -63,8 +55,6 @@
     },
     "node_modules/@asamuzakjp/dom-selector/node_modules/lru-cache": {
       "version": "11.2.7",
-      "resolved": "https://registry.npmjs.org/lru-cache/-/lru-cache-11.2.7.tgz",
-      "integrity": "sha512-aY/R+aEsRelme17KGQa/1ZSIpLpNYYrhcrepKTZgE+W3WM16YMCaPwOHLHsmopZHELU0Ojin1lPVxKR0MihncA==",
       "dev": true,
       "license": "BlueOak-1.0.0",
       "engines": {
@@ -73,8 +63,6 @@
     },
     "node_modules/@asamuzakjp/nwsapi": {
       "version": "2.3.9",
-      "resolved": "https://registry.npmjs.org/@asamuzakjp/nwsapi/-/nwsapi-2.3.9.tgz",
-      "integrity": "sha512-n8GuYSrI9bF7FFZ/SjhwevlHc8xaVlb/7HmHelnc/PZXBD2ZR49NnN9sMMuDdEGPeeRQ5d0hqlSlEpgCX3Wl0Q==",
       "dev": true,
       "license": "MIT"
     },
@@ -458,8 +446,6 @@
     },
     "node_modules/@csstools/color-helpers": {
       "version": "6.0.2",
-      "resolved": "https://registry.npmjs.org/@csstools/color-helpers/-/color-helpers-6.0.2.tgz",
-      "integrity": "sha512-LMGQLS9EuADloEFkcTBR3BwV/CGHV7zyDxVRtVDTwdI2Ca4it0CCVTT9wCkxSgokjE5Ho41hEPgb8OEUwoXr6Q==",
       "dev": true,
       "funding": [
         {
@@ -478,8 +464,6 @@
     },
     "node_modules/@csstools/css-calc": {
       "version": "3.1.1",
-      "resolved": "https://registry.npmjs.org/@csstools/css-calc/-/css-calc-3.1.1.tgz",
-      "integrity": "sha512-HJ26Z/vmsZQqs/o3a6bgKslXGFAungXGbinULZO3eMsOyNJHeBBZfup5FiZInOghgoM4Hwnmw+OgbJCNg1wwUQ==",
       "dev": true,
       "funding": [
         {
@@ -502,8 +486,6 @@
     },
     "node_modules/@csstools/css-color-parser": {
       "version": "4.0.2",
-      "resolved": "https://registry.npmjs.org/@csstools/css-color-parser/-/css-color-parser-4.0.2.tgz",
-      "integrity": "sha512-0GEfbBLmTFf0dJlpsNU7zwxRIH0/BGEMuXLTCvFYxuL1tNhqzTbtnFICyJLTNK4a+RechKP75e7w42ClXSnJQw==",
       "dev": true,
       "funding": [
         {
@@ -530,8 +512,6 @@
     },
     "node_modules/@csstools/css-parser-algorithms": {
       "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/@csstools/css-parser-algorithms/-/css-parser-algorithms-4.0.0.tgz",
-      "integrity": "sha512-+B87qS7fIG3L5h3qwJ/IFbjoVoOe/bpOdh9hAjXbvx0o8ImEmUsGXN0inFOnk2ChCFgqkkGFQ+TpM5rbhkKe4w==",
       "dev": true,
       "funding": [
         {
@@ -553,8 +533,6 @@
     },
     "node_modules/@csstools/css-syntax-patches-for-csstree": {
       "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/@csstools/css-syntax-patches-for-csstree/-/css-syntax-patches-for-csstree-1.1.1.tgz",
-      "integrity": "sha512-BvqN0AMWNAnLk9G8jnUT77D+mUbY/H2b3uDTvg2isJkHaOufUE2R3AOwxWo7VBQKT1lOdwdvorddo2B/lk64+w==",
       "dev": true,
       "funding": [
         {
@@ -578,8 +556,6 @@
     },
     "node_modules/@csstools/css-tokenizer": {
       "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/@csstools/css-tokenizer/-/css-tokenizer-4.0.0.tgz",
-      "integrity": "sha512-QxULHAm7cNu72w97JUNCBFODFaXpbDg+dP8b/oWFAZ2MTRppA3U00Y2L1HqaS4J6yBqxwa/Y3nMBaxVKbB/NsA==",
       "dev": true,
       "funding": [
         {
@@ -598,8 +574,6 @@
     },
     "node_modules/@exodus/bytes": {
       "version": "1.15.0",
-      "resolved": "https://registry.npmjs.org/@exodus/bytes/-/bytes-1.15.0.tgz",
-      "integrity": "sha512-UY0nlA+feH81UGSHv92sLEPLCeZFjXOuHhrIo0HQydScuQc8s0A7kL/UdgwgDq8g8ilksmuoF35YVTNphV2aBQ==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -732,8 +706,6 @@
     },
     "node_modules/bidi-js": {
       "version": "1.0.3",
-      "resolved": "https://registry.npmjs.org/bidi-js/-/bidi-js-1.0.3.tgz",
-      "integrity": "sha512-RKshQI1R3YQ+n9YJz2QQ147P66ELpa1FQEg20Dk8oW9t2KgLbpDLLp9aGZ7y8WHSshDknG0bknqGw5/tyCs5tw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -891,8 +863,6 @@
     },
     "node_modules/css-tree": {
       "version": "3.2.1",
-      "resolved": "https://registry.npmjs.org/css-tree/-/css-tree-3.2.1.tgz",
-      "integrity": "sha512-X7sjQzceUhu1u7Y/ylrRZFU2FS6LRiFVp6rKLPg23y3x3c3DOKAwuXGDp+PAGjh6CSnCjYeAul8pcT8bAl+lSA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -905,8 +875,6 @@
     },
     "node_modules/cssstyle": {
       "version": "5.3.7",
-      "resolved": "https://registry.npmjs.org/cssstyle/-/cssstyle-5.3.7.tgz",
-      "integrity": "sha512-7D2EPVltRrsTkhpQmksIu+LxeWAIEk6wRDMJ1qljlv+CKHJM+cJLlfhWIzNA44eAsHXSNe3+vO6DW1yCYx8SuQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -932,8 +900,6 @@
     },
     "node_modules/data-urls": {
       "version": "6.0.1",
-      "resolved": "https://registry.npmjs.org/data-urls/-/data-urls-6.0.1.tgz",
-      "integrity": "sha512-euIQENZg6x8mj3fO6o9+fOW8MimUI4PpD/fZBhJfeioZVy9TUpM4UY7KjQNVZFlqwJ0UdzRDzkycB997HEq1BQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -946,8 +912,6 @@
     },
     "node_modules/data-urls/node_modules/whatwg-mimetype": {
       "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/whatwg-mimetype/-/whatwg-mimetype-5.0.0.tgz",
-      "integrity": "sha512-sXcNcHOC51uPGF0P/D4NVtrkjSU2fNsm9iog4ZvZJsL3rjoDAzXZhkm2MWt1y+PUdggKAYVoMAIYcs78wJ51Cw==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -972,8 +936,6 @@
     },
     "node_modules/decimal.js": {
       "version": "10.6.0",
-      "resolved": "https://registry.npmjs.org/decimal.js/-/decimal.js-10.6.0.tgz",
-      "integrity": "sha512-YpgQiITW3JXGntzdUmyUR1V812Hn8T1YVXhCu+wO3OpS4eU9l4YdD3qjyiKdV6mvV29zapkMeD390UVEf2lkUg==",
       "dev": true,
       "license": "MIT"
     },
@@ -1074,6 +1036,24 @@
         "node": ">=16"
       }
     },
+    "node_modules/git-semver-tags": {
+      "version": "7.0.1",
+      "resolved": "https://registry.npmjs.org/git-semver-tags/-/git-semver-tags-7.0.1.tgz",
+      "integrity": "sha512-NY0ZHjJzyyNXHTDZmj+GG7PyuAKtMsyWSwh07CR2hOZFa+/yoTsXci/nF2obzL8UDhakFNkD9gNdt/Ed+cxh2Q==",
+      "deprecated": "This package is no longer maintained. For the JavaScript API, please use @conventional-changelog/git-client instead.",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "meow": "^12.0.1",
+        "semver": "^7.5.2"
+      },
+      "bin": {
+        "git-semver-tags": "cli.mjs"
+      },
+      "engines": {
+        "node": ">=16"
+      }
+    },
     "node_modules/glob": {
       "version": "13.0.0",
       "dev": true,
@@ -1113,14 +1093,14 @@
       }
     },
     "node_modules/google-closure-compiler": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler/-/google-closure-compiler-20260315.0.0.tgz",
-      "integrity": "sha512-z+Zdkth5+bdt+bSy3HuYRgjSAgx4WncBZ0Rd+/1Hf3wFemkkTxXGXpG7A5Y8n5WrTsPd1n/fxVuD5xfFL6s5Dw==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler/-/google-closure-compiler-20260330.0.0.tgz",
+      "integrity": "sha512-USY3fekBavIfAkzHEooo6FcuTT/+z6FbfMRK3l3nsgsKB2oJ4baPPz2XYGSivHNstB8l10CcPvWh5FwlWZpzvQ==",
       "dev": true,
       "license": "Apache-2.0",
       "dependencies": {
         "chalk": "^2.0.0 || ^3.0.0 || ^4.0.0 || ^5.0.0 <5.6.1 || ^5.6.2 >5.6.1",
-        "google-closure-compiler-java": "^20260315.0.0",
+        "google-closure-compiler-java": "^20260330.0.0",
         "minimist": "^1.0.0",
         "vinyl": "^3.0.1",
         "vinyl-sourcemaps-apply": "^0.2.0"
@@ -1132,23 +1112,23 @@
         "node": ">=18"
       },
       "optionalDependencies": {
-        "google-closure-compiler-linux": "^20260315.0.0",
-        "google-closure-compiler-linux-arm64": "^20260315.0.0",
-        "google-closure-compiler-macos": "^20260315.0.0",
-        "google-closure-compiler-windows": "^20260315.0.0"
+        "google-closure-compiler-linux": "^20260330.0.0",
+        "google-closure-compiler-linux-arm64": "^20260330.0.0",
+        "google-closure-compiler-macos": "^20260330.0.0",
+        "google-closure-compiler-windows": "^20260330.0.0"
       }
     },
     "node_modules/google-closure-compiler-java": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler-java/-/google-closure-compiler-java-20260315.0.0.tgz",
-      "integrity": "sha512-3CYSN3x7S7xCc/7Yx9vmH4pOc/8tkJdPjftUV1tUt2/tYKYEeH9mGv5dtrs22Uf6qXdIqlEBGg+ZQXX13xVpww==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler-java/-/google-closure-compiler-java-20260330.0.0.tgz",
+      "integrity": "sha512-wc+HpQlNvS5mquzVjpOjhVlgYgvxnOyqPDCJJN2k7+5dVE7mbzZya7mIEfsPaRZ39KbPVvNrDpMEAahKiuNtjA==",
       "dev": true,
       "license": "Apache-2.0"
     },
     "node_modules/google-closure-compiler-linux": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler-linux/-/google-closure-compiler-linux-20260315.0.0.tgz",
-      "integrity": "sha512-jXUnyY3Cr5kmBDmGuxw3HULjzX69AeXVRcIpI+YuFGfo8qX1dIbkOpNK7JHWtJ7qE01foGmCwjnx5WOSrplYyg==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler-linux/-/google-closure-compiler-linux-20260330.0.0.tgz",
+      "integrity": "sha512-BWEknhsCj/zero4Zk0/FtbAM1eO3QQA34xGQa4HeREV36trs/zmVCSVRqYCYcEAAEBiMjj97wMPdhFSkm72k8g==",
       "cpu": [
         "x32",
         "x64"
@@ -1161,9 +1141,9 @@
       ]
     },
     "node_modules/google-closure-compiler-linux-arm64": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler-linux-arm64/-/google-closure-compiler-linux-arm64-20260315.0.0.tgz",
-      "integrity": "sha512-e0dSgFEg/bE9gscw+u2Roy/FkJOQ/6MvG3nBCPR8IqAkJ+ibBAQKnYOSK1sAUp1bXJROiUJy6a+GTJ312FKS+A==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler-linux-arm64/-/google-closure-compiler-linux-arm64-20260330.0.0.tgz",
+      "integrity": "sha512-7C9khLgtZEUfZ/xCkjLVTC5vRJt5CmfWwiAk/u3+pPzsDubngHwKE1e0UTPqNwJEXo8VVXM4OdvrY7hzwR4MZg==",
       "cpu": [
         "arm64"
       ],
@@ -1175,9 +1155,9 @@
       ]
     },
     "node_modules/google-closure-compiler-macos": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler-macos/-/google-closure-compiler-macos-20260315.0.0.tgz",
-      "integrity": "sha512-yhY46Mdbqs7HAPsYAhXlt9Q2rROLZfaZrTFZZqyVo/uufEmGH3vOyxshTbBQWhaJQHkELWsc/XKSVfvX4rcoYA==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler-macos/-/google-closure-compiler-macos-20260330.0.0.tgz",
+      "integrity": "sha512-3mGI7eYwIZYAZFdMwpS4wXB5+q/kKbl936FtvRIIgRtFhSX7m6kwsyXqGP62ZvuOCcPcW14dC6k7g6l7eS2Fgw==",
       "cpu": [
         "arm64"
       ],
@@ -1189,9 +1169,9 @@
       ]
     },
     "node_modules/google-closure-compiler-windows": {
-      "version": "20260315.0.0",
-      "resolved": "https://registry.npmjs.org/google-closure-compiler-windows/-/google-closure-compiler-windows-20260315.0.0.tgz",
-      "integrity": "sha512-EpIPPU6vQ5EzuzKQMe3vhEWLqqXY4SKNoLjXrr4GWXoses9h7xT6nkHDuDe/7x5MWZOMRv4qmlW3PzLCsx98qg==",
+      "version": "20260330.0.0",
+      "resolved": "https://registry.npmjs.org/google-closure-compiler-windows/-/google-closure-compiler-windows-20260330.0.0.tgz",
+      "integrity": "sha512-dqMKvjzdAlgERhHKHG12dKrOcL2ASNeKP1c3doCQn3vwZizz1xV2Ns6m711tb6pfNXFstfR6VJAoMuv/BjmdYQ==",
       "cpu": [
         "x32",
         "x64"
@@ -1333,8 +1313,6 @@
     },
     "node_modules/jsdom": {
       "version": "27.4.0",
-      "resolved": "https://registry.npmjs.org/jsdom/-/jsdom-27.4.0.tgz",
-      "integrity": "sha512-mjzqwWRD9Y1J1KUi7W97Gja1bwOOM5Ug0EZ6UDK3xS7j7mndrkwozHtSblfomlzyB4NepioNt+B2sOSzczVgtQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1373,8 +1351,6 @@
     },
     "node_modules/jsdom/node_modules/entities": {
       "version": "6.0.1",
-      "resolved": "https://registry.npmjs.org/entities/-/entities-6.0.1.tgz",
-      "integrity": "sha512-aN97NXWF6AWBTahfVOIrB/NShkzi5H7F9r1s9mD3cDj4Ko5f2qhhVoYMibXF7GlLveb/D2ioWay8lxI97Ven3g==",
       "dev": true,
       "license": "BSD-2-Clause",
       "engines": {
@@ -1386,8 +1362,6 @@
     },
     "node_modules/jsdom/node_modules/html-encoding-sniffer": {
       "version": "6.0.0",
-      "resolved": "https://registry.npmjs.org/html-encoding-sniffer/-/html-encoding-sniffer-6.0.0.tgz",
-      "integrity": "sha512-CV9TW3Y3f8/wT0BRFc1/KAVQ3TUHiXmaAb6VW9vtiMFf7SLoMd1PdAc4W3KFOFETBJUb90KatHqlsZMWV+R9Gg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1399,8 +1373,6 @@
     },
     "node_modules/jsdom/node_modules/parse5": {
       "version": "8.0.0",
-      "resolved": "https://registry.npmjs.org/parse5/-/parse5-8.0.0.tgz",
-      "integrity": "sha512-9m4m5GSgXjL4AjumKzq1Fgfp3Z8rsvjRNbnkVwfu2ImRqE5D0LnY2QfDen18FSY9C573YU5XxSapdHZTZ2WolA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1503,8 +1475,6 @@
     },
     "node_modules/mdn-data": {
       "version": "2.27.1",
-      "resolved": "https://registry.npmjs.org/mdn-data/-/mdn-data-2.27.1.tgz",
-      "integrity": "sha512-9Yubnt3e8A0OKwxYSXyhLymGW4sCufcLG6VdiDdUGVkPhpqLxlvP5vl1983gQjJl3tqbrM731mjaZaP68AgosQ==",
       "dev": true,
       "license": "CC0-1.0"
     },
@@ -1668,6 +1638,20 @@
         "node": ">=v12.22.7"
       }
     },
+    "node_modules/semver": {
+      "version": "7.5.4",
+      "dev": true,
+      "license": "ISC",
+      "dependencies": {
+        "lru-cache": "^6.0.0"
+      },
+      "bin": {
+        "semver": "bin/semver.js"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
     "node_modules/source-map": {
       "version": "0.5.7",
       "dev": true,
@@ -1678,8 +1662,6 @@
     },
     "node_modules/source-map-js": {
       "version": "1.2.1",
-      "resolved": "https://registry.npmjs.org/source-map-js/-/source-map-js-1.2.1.tgz",
-      "integrity": "sha512-UXWMKhLOwVKb728IUtQPXxfYU+usdybtUrK/8uGE8CQMvrhOpwvzDBwj0QhSL7MQc7vIsISBG8VQ8+IDQxpfQA==",
       "dev": true,
       "license": "BSD-3-Clause",
       "engines": {
@@ -1772,8 +1754,6 @@
     },
     "node_modules/tldts": {
       "version": "7.0.26",
-      "resolved": "https://registry.npmjs.org/tldts/-/tldts-7.0.26.tgz",
-      "integrity": "sha512-WiGwQjr0qYdNNG8KpMKlSvpxz652lqa3Rd+/hSaDcY4Uo6SKWZq2LAF+hsAhUewTtYhXlorBKgNF3Kk8hnjGoQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1785,15 +1765,11 @@
     },
     "node_modules/tldts-core": {
       "version": "7.0.26",
-      "resolved": "https://registry.npmjs.org/tldts-core/-/tldts-core-7.0.26.tgz",
-      "integrity": "sha512-5WJ2SqFsv4G2Dwi7ZFVRnz6b2H1od39QME1lc2y5Ew3eWiZMAeqOAfWpRP9jHvhUl881406QtZTODvjttJs+ew==",
       "dev": true,
       "license": "MIT"
     },
     "node_modules/tough-cookie": {
       "version": "6.0.1",
-      "resolved": "https://registry.npmjs.org/tough-cookie/-/tough-cookie-6.0.1.tgz",
-      "integrity": "sha512-LktZQb3IeoUWB9lqR5EWTHgW/VTITCXg4D21M+lvybRVdylLrRMnqaIONLVb5mav8vM19m44HIcGq4qASeu2Qw==",
       "dev": true,
       "license": "BSD-3-Clause",
       "dependencies": {
@@ -1805,8 +1781,6 @@
     },
     "node_modules/tr46": {
       "version": "6.0.0",
-      "resolved": "https://registry.npmjs.org/tr46/-/tr46-6.0.0.tgz",
-      "integrity": "sha512-bLVMLPtstlZ4iMQHpFHTR7GAGj2jxi8Dg0s2h2MafAE4uSWF98FC/3MomU51iQAMf8/qDUbKWf5GxuvvVcXEhw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1867,8 +1841,6 @@
     },
     "node_modules/webidl-conversions": {
       "version": "8.0.1",
-      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-8.0.1.tgz",
-      "integrity": "sha512-BMhLD/Sw+GbJC21C/UgyaZX41nPt8bUTg+jWyDeg7e7YN4xOM05YPSIXceACnXVtqyEw/LMClUQMtMZ+PGGpqQ==",
       "dev": true,
       "license": "BSD-2-Clause",
       "engines": {
@@ -1885,8 +1857,6 @@
     },
     "node_modules/whatwg-url": {
       "version": "15.1.0",
-      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-15.1.0.tgz",
-      "integrity": "sha512-2ytDk0kiEj/yu90JOAp44PVPUkO9+jVhyf+SybKlRHSDlvOOZhdPIrr7xTH64l4WixO2cP+wQIcgujkGBPPz6g==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1980,7 +1950,7 @@
       }
     },
     "packages/blockly": {
-      "version": "12.4.1",
+      "version": "12.5.1",
       "hasInstallScript": true,
       "license": "Apache-2.0",
       "devDependencies": {
@@ -1995,6 +1965,8 @@
         "async-done": "^2.0.0",
         "chai": "^6.0.1",
         "concurrently": "^9.0.1",
+        "conventional-changelog-conventionalcommits": "^7.0.2",
+        "conventional-recommended-bump": "^9.0.0",
         "eslint": "^9.15.0",
         "eslint-config-google": "^0.14.0",
         "eslint-config-prettier": "^10.1.1",
@@ -2003,16 +1975,13 @@
         "eslint-plugin-prettier": "^5.2.1",
         "glob": "^11.0.1",
         "globals": "^16.0.0",
-        "google-closure-compiler": "^20260315.0.0",
+        "google-closure-compiler": "^20260330.0.0",
         "gulp": "^5.0.0",
         "gulp-concat": "^2.6.1",
         "gulp-gzip": "^1.4.2",
         "gulp-header": "^2.0.9",
-        "gulp-insert": "^0.5.0",
         "gulp-rename": "^2.0.0",
         "gulp-replace": "^1.0.0",
-        "gulp-series": "^1.0.2",
-        "gulp-shell": "^0.8.0",
         "gulp-sourcemaps": "^3.0.0",
         "gulp-umd": "^2.0.0",
         "http-server": "^14.0.0",
@@ -4698,6 +4667,47 @@
         "node": ">= 0.6"
       }
     },
+    "packages/blockly/node_modules/conventional-changelog-preset-loader": {
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/conventional-changelog-preset-loader/-/conventional-changelog-preset-loader-4.1.0.tgz",
+      "integrity": "sha512-HozQjJicZTuRhCRTq4rZbefaiCzRM2pr6u2NL3XhrmQm4RMnDXfESU6JKu/pnKwx5xtdkYfNCsbhN5exhiKGJA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=16"
+      }
+    },
+    "packages/blockly/node_modules/conventional-commits-filter": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/conventional-commits-filter/-/conventional-commits-filter-4.0.0.tgz",
+      "integrity": "sha512-rnpnibcSOdFcdclpFwWa+pPlZJhXE7l+XK04zxhbWrhgpR96h33QLz8hITTXbcYICxVr3HZFtbtUAQ+4LdBo9A==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=16"
+      }
+    },
+    "packages/blockly/node_modules/conventional-recommended-bump": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/conventional-recommended-bump/-/conventional-recommended-bump-9.0.0.tgz",
+      "integrity": "sha512-HR1yD0G5HgYAu6K0wJjLd7QGRK8MQDqqj6Tn1n/ja1dFwBCE6QmV+iSgQ5F7hkx7OUR/8bHpxJqYtXj2f/opPQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "conventional-changelog-preset-loader": "^4.1.0",
+        "conventional-commits-filter": "^4.0.0",
+        "conventional-commits-parser": "^5.0.0",
+        "git-raw-commits": "^4.0.0",
+        "git-semver-tags": "^7.0.0",
+        "meow": "^12.0.1"
+      },
+      "bin": {
+        "conventional-recommended-bump": "cli.mjs"
+      },
+      "engines": {
+        "node": ">=16"
+      }
+    },
     "packages/blockly/node_modules/convert-source-map": {
       "version": "1.8.0",
       "dev": true,
@@ -6525,36 +6535,6 @@
         "xtend": "~4.0.1"
       }
     },
-    "packages/blockly/node_modules/gulp-insert": {
-      "version": "0.5.0",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "readable-stream": "^1.0.26-4",
-        "streamqueue": "0.0.6"
-      }
-    },
-    "packages/blockly/node_modules/gulp-insert/node_modules/isarray": {
-      "version": "0.0.1",
-      "dev": true,
-      "license": "MIT"
-    },
-    "packages/blockly/node_modules/gulp-insert/node_modules/readable-stream": {
-      "version": "1.1.14",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "core-util-is": "~1.0.0",
-        "inherits": "~2.0.1",
-        "isarray": "0.0.1",
-        "string_decoder": "~0.10.x"
-      }
-    },
-    "packages/blockly/node_modules/gulp-insert/node_modules/string_decoder": {
-      "version": "0.10.31",
-      "dev": true,
-      "license": "MIT"
-    },
     "packages/blockly/node_modules/gulp-rename": {
       "version": "2.1.0",
       "dev": true,
@@ -6578,48 +6558,6 @@
         "node": ">=10"
       }
     },
-    "packages/blockly/node_modules/gulp-series": {
-      "version": "1.0.2",
-      "dev": true,
-      "license": "MIT"
-    },
-    "packages/blockly/node_modules/gulp-shell": {
-      "version": "0.8.0",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "chalk": "^3.0.0",
-        "fancy-log": "^1.3.3",
-        "lodash.template": "^4.5.0",
-        "plugin-error": "^1.0.1",
-        "through2": "^3.0.1",
-        "tslib": "^1.10.0"
-      },
-      "engines": {
-        "node": ">=10.0.0"
-      }
-    },
-    "packages/blockly/node_modules/gulp-shell/node_modules/chalk": {
-      "version": "3.0.0",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "ansi-styles": "^4.1.0",
-        "supports-color": "^7.1.0"
-      },
-      "engines": {
-        "node": ">=8"
-      }
-    },
-    "packages/blockly/node_modules/gulp-shell/node_modules/through2": {
-      "version": "3.0.2",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "inherits": "^2.0.4",
-        "readable-stream": "2 || 3"
-      }
-    },
     "packages/blockly/node_modules/gulp-sourcemaps": {
       "version": "3.0.0",
       "dev": true,
@@ -9075,37 +9013,6 @@
         "any-promise": "^1.1.0"
       }
     },
-    "packages/blockly/node_modules/streamqueue": {
-      "version": "0.0.6",
-      "dev": true,
-      "dependencies": {
-        "readable-stream": "^1.0.26-2"
-      },
-      "engines": {
-        "node": ">= 0.10.0"
-      }
-    },
-    "packages/blockly/node_modules/streamqueue/node_modules/isarray": {
-      "version": "0.0.1",
-      "dev": true,
-      "license": "MIT"
-    },
-    "packages/blockly/node_modules/streamqueue/node_modules/readable-stream": {
-      "version": "1.1.14",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "core-util-is": "~1.0.0",
-        "inherits": "~2.0.1",
-        "isarray": "0.0.1",
-        "string_decoder": "~0.10.x"
-      }
-    },
-    "packages/blockly/node_modules/streamqueue/node_modules/string_decoder": {
-      "version": "0.10.31",
-      "dev": true,
-      "license": "MIT"
-    },
     "packages/blockly/node_modules/string_decoder": {
       "version": "1.1.1",
       "dev": true,
@@ -9339,11 +9246,6 @@
         "typescript": ">=4.8.4"
       }
     },
-    "packages/blockly/node_modules/tslib": {
-      "version": "1.14.1",
-      "dev": true,
-      "license": "0BSD"
-    },
     "packages/blockly/node_modules/type": {
       "version": "1.2.0",
       "dev": true,
diff --git a/packages/blockly/core/connection.ts b/packages/blockly/core/connection.ts
index a55c25059..a79b7b9b1 100644
--- a/packages/blockly/core/connection.ts
+++ b/packages/blockly/core/connection.ts
@@ -291,10 +291,7 @@ export class Connection {
     }
 
     let event;
-    if (
-      eventUtils.isEnabled() &&
-      !childConnection.getSourceBlock().isDeadOrDying()
-    ) {
+    if (eventUtils.isEnabled()) {
       event = new (eventUtils.get(EventType.BLOCK_MOVE))(
         childConnection.getSourceBlock(),
       ) as BlockMove;
diff --git a/packages/blockly/core/css.ts b/packages/blockly/core/css.ts
index c664d25f8..0384f719f 100644
--- a/packages/blockly/core/css.ts
+++ b/packages/blockly/core/css.ts
@@ -98,14 +98,7 @@ const content = `
 
 .blocklyBlockCanvas.blocklyCanvasTransitioning,
 .blocklyBubbleCanvas.blocklyCanvasTransitioning {
-  transition: transform .15s;
-}
-
-@media (prefers-reduced-motion) {
-  .blocklyBlockCanvas.blocklyCanvasTransitioning,
-  .blocklyBubbleCanvas.blocklyCanvasTransitioning {
-    transition: none;
-  }
+  transition: transform .5s;
 }
 
 .blocklyEmboss {
@@ -466,17 +459,14 @@ input[type=number] {
 }
 
 /* State: selected/checked. */
-.blocklyMenuItemCheckbox {
-  height: 16px;
-  position: absolute;
-  width: 16px;
-}
-
 .blocklyMenuItemSelected .blocklyMenuItemCheckbox {
   background: url(<<<PATH>>>/sprites.svg) no-repeat -48px -16px;
   float: left;
   margin-left: -24px;
+  width: 16px;
+  height: 16px;
   position: static;  /* Scroll with the menu. */
+  display: block;
 }
 
 .blocklyMenuItemRtl .blocklyMenuItemCheckbox {
diff --git a/packages/blockly/core/layer_manager.ts b/packages/blockly/core/layer_manager.ts
index 7d253b110..1142bcf58 100644
--- a/packages/blockly/core/layer_manager.ts
+++ b/packages/blockly/core/layer_manager.ts
@@ -73,11 +73,11 @@ export class LayerManager {
    * @internal
    */
   appendToAnimationLayer(elem: IRenderedElement) {
-    const currentTransform = this.dragLayer?.style.transform;
+    const currentTransform = this.dragLayer?.getAttribute('transform');
     // Only update the current transform when appending, so animations don't
     // move if the workspace moves.
-    if (currentTransform && this.animationLayer) {
-      this.animationLayer.style.transform = currentTransform;
+    if (currentTransform) {
+      this.animationLayer?.setAttribute('transform', currentTransform);
     }
     this.animationLayer?.appendChild(elem.getSvgRoot());
   }
@@ -88,12 +88,10 @@ export class LayerManager {
    * @internal
    */
   translateLayers(newCoord: Coordinate, newScale: number) {
-    const translation = `translate(${newCoord.x}px, ${newCoord.y}px) scale(${newScale})`;
-    if (this.dragLayer) {
-      this.dragLayer.style.transform = translation;
-    }
+    const translation = `translate(${newCoord.x}, ${newCoord.y}) scale(${newScale})`;
+    this.dragLayer?.setAttribute('transform', translation);
     for (const [_, layer] of this.layers) {
-      layer.style.transform = translation;
+      layer.setAttribute('transform', translation);
     }
   }
 
diff --git a/packages/blockly/core/toolbox/toolbox.ts b/packages/blockly/core/toolbox/toolbox.ts
index 28861f231..67bb0fc84 100644
--- a/packages/blockly/core/toolbox/toolbox.ts
+++ b/packages/blockly/core/toolbox/toolbox.ts
@@ -11,7 +11,6 @@
  */
 // Former goog.module ID: Blockly.Toolbox
 
-// Unused import preserved for side-effects. Remove if unneeded.
 import {BlockSvg} from '../block_svg.js';
 import * as browserEvents from '../browser_events.js';
 import * as common from '../common.js';
@@ -199,7 +198,7 @@ export class Toolbox
     aria.setRole(this.contentsDiv_, aria.Role.TREE);
     container.appendChild(this.contentsDiv_);
 
-    svg.parentNode!.insertBefore(container, svg);
+    svg.parentNode?.insertBefore(container, svg);
 
     this.attachEvents_(container, this.contentsDiv_);
     return container;
@@ -288,7 +287,7 @@ export class Toolbox
       const itemId = (targetElement as Element).getAttribute('id');
       if (itemId) {
         const item = this.getToolboxItemById(itemId);
-        if (item!.isSelectable()) {
+        if (item?.isSelectable()) {
           this.setSelectedItem(item);
           (item as ISelectableToolboxItem).onClick(e);
         }
@@ -380,7 +379,7 @@ export class Toolbox
       const toolboxItemDef = toolboxDef[i];
       this.createToolboxItem(toolboxItemDef, fragment);
     }
-    this.contentsDiv_!.appendChild(fragment);
+    this.contentsDiv_?.appendChild(fragment);
   }
 
   /**
@@ -419,9 +418,7 @@ export class Toolbox
       }
       // Adds the ID to the HTML element that can receive a click.
       // This is used in onClick_ to find the toolboxItem that was clicked.
-      if (toolboxItem.getClickTarget()) {
-        toolboxItem.getClickTarget()!.setAttribute('id', toolboxItem.getId());
-      }
+      toolboxItem.getClickTarget()?.setAttribute('id', toolboxItem.getId());
     }
   }
 
@@ -706,7 +703,7 @@ export class Toolbox
       this.width_ = toolboxDiv.offsetWidth;
       this.height_ = workspaceMetrics.viewHeight;
     }
-    this.flyout!.position();
+    this.flyout?.position();
   }
 
   /**
@@ -715,10 +712,11 @@ export class Toolbox
    * @internal
    */
   handleToolboxItemResize() {
+    if (!this.HtmlDiv) return;
     // Reposition the workspace so that (0,0) is in the correct position
     // relative to the new absolute edge (ie toolbox edge).
     const workspace = this.workspace_;
-    const rect = this.HtmlDiv!.getBoundingClientRect();
+    const rect = this.HtmlDiv.getBoundingClientRect();
     const flyout = this.getFlyout();
     const newX =
       this.toolboxPosition === toolbox.Position.LEFT
@@ -770,7 +768,7 @@ export class Toolbox
       this.selectedItem_.isSelectable() &&
       this.selectedItem_.getContents().length
     ) {
-      this.flyout!.show(this.selectedItem_.getContents());
+      this.flyout?.show(this.selectedItem_.getContents());
     }
   }
 
@@ -784,7 +782,9 @@ export class Toolbox
       return;
     }
 
-    this.HtmlDiv!.style.display = isVisible ? 'block' : 'none';
+    if (this.HtmlDiv) {
+      this.HtmlDiv.style.display = isVisible ? 'block' : 'none';
+    }
     this.isVisible_ = isVisible;
     // Invisible toolbox is ignored as drag targets and must have the drag
     // target updated.
@@ -928,10 +928,10 @@ export class Toolbox
       (oldItem === newItem && !newItem.isCollapsible()) ||
       !newItem.getContents().length
     ) {
-      this.flyout!.hide();
+      this.flyout?.hide();
     } else {
-      this.flyout!.show(newItem.getContents());
-      this.flyout!.scrollToStart();
+      this.flyout?.show(newItem.getContents());
+      this.flyout?.scrollToStart();
     }
   }
 
@@ -968,8 +968,8 @@ export class Toolbox
   private toggleSelectedItem(expanded: boolean): boolean {
     if (
       isCollapsibleToolboxItem(this.selectedItem_) &&
-      this.selectedItem_.isCollapsible() &&
-      this.selectedItem_.isExpanded() !== expanded
+      this.selectedItem_?.isCollapsible() &&
+      this.selectedItem_?.isExpanded() !== expanded
     ) {
       this.selectedItem_.toggleExpanded();
       return true;
@@ -981,7 +981,7 @@ export class Toolbox
   /** Disposes of this toolbox. */
   dispose() {
     this.workspace_.getComponentManager().removeComponent('toolbox');
-    this.flyout!.dispose();
+    this.flyout?.dispose();
     this.contents.forEach((item) => item.dispose());
 
     for (let j = 0; j < this.boundEvents_.length; j++) {
diff --git a/packages/blockly/core/zoom_controls.ts b/packages/blockly/core/zoom_controls.ts
index 6bd119423..4f14b73be 100644
--- a/packages/blockly/core/zoom_controls.ts
+++ b/packages/blockly/core/zoom_controls.ts
@@ -373,10 +373,8 @@ export class ZoomControls implements IPositionable {
    * @param e A mouse down event.
    */
   private zoom(amount: number, e: PointerEvent) {
-    this.workspace.beginCanvasTransition();
     this.workspace.markFocused();
     this.workspace.zoomCenter(amount);
-    setTimeout(this.workspace.endCanvasTransition.bind(this.workspace), 150);
     this.fireZoomEvent();
     Touch.clearTouchIdentifier(); // Don't block future drags.
     e.stopPropagation(); // Don't start a workspace scroll.
@@ -461,7 +459,7 @@ export class ZoomControls implements IPositionable {
     this.workspace.zoomCenter(amount);
     this.workspace.scrollCenter();
 
-    setTimeout(this.workspace.endCanvasTransition.bind(this.workspace), 150);
+    setTimeout(this.workspace.endCanvasTransition.bind(this.workspace), 500);
     this.fireZoomEvent();
     Touch.clearTouchIdentifier(); // Don't block future drags.
     e.stopPropagation(); // Don't start a workspace scroll.
diff --git a/packages/blockly/gulpfile.mjs b/packages/blockly/gulpfile.mjs
index ad61bcb51..378d6ce5e 100644
--- a/packages/blockly/gulpfile.mjs
+++ b/packages/blockly/gulpfile.mjs
@@ -33,18 +33,9 @@ import {
   tsc,
 } from './scripts/gulpfiles/build_tasks.mjs';
 import {docs} from './scripts/gulpfiles/docs_tasks.mjs';
-import {
-  createRC,
-  syncDevelop,
-  syncMaster,
-  updateGithubPages,
-} from './scripts/gulpfiles/git_tasks.mjs';
+import {updateGithubPages} from './scripts/gulpfiles/git_tasks.mjs';
 import {cleanReleaseDir, pack} from './scripts/gulpfiles/package_tasks.mjs';
-import {
-  publish,
-  publishBeta,
-  recompile,
-} from './scripts/gulpfiles/release_tasks.mjs';
+import {publish, publishBeta} from './scripts/gulpfiles/release_tasks.mjs';
 import {
   generators,
   interactiveMocha,
@@ -72,7 +63,7 @@ export {
   prepareDemos,
   deployDemosBeta,
   deployDemos,
-  updateGithubPages as gitUpdateGithubPages,
+  updateGithubPages,
 }
 
 // Manually-invokable targets that also invoke prerequisites where
@@ -86,15 +77,5 @@ export {
   generators as testGenerators,
   interactiveMocha,
   buildAdvancedCompilationTest,
-  createRC as gitCreateRC,
   docs,
 }
-
-// Legacy targets, to be deleted.
-//
-// prettier-ignore
-export {
-  recompile,
-  syncDevelop as gitSyncDevelop,
-  syncMaster as gitSyncMaster,
-}
diff --git a/packages/blockly/package.json b/packages/blockly/package.json
index 5ab927b43..7f6d53970 100644
--- a/packages/blockly/package.json
+++ b/packages/blockly/package.json
@@ -1,16 +1,16 @@
 {
   "name": "blockly",
-  "version": "12.4.1",
+  "version": "12.5.1",
   "description": "Blockly is a library for building visual programming editors.",
   "keywords": [
     "blockly"
   ],
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/google/blockly.git"
+    "url": "git+https://github.com/RaspberryPiFoundation/blockly.git"
   },
   "bugs": {
-    "url": "https://github.com/google/blockly/issues"
+    "url": "https://github.com/RaspberryPiFoundation/blockly/issues"
   },
   "homepage": "https://developers.google.com/blockly/",
   "author": {
@@ -41,8 +41,6 @@
     "prepareDemos": "gulp prepareDemos",
     "publish": "npm ci && gulp publish",
     "publish:beta": "npm ci && gulp publishBeta",
-    "recompile": "gulp recompile",
-    "release": "gulp gitCreateRC",
     "start": "npm run build && concurrently -n tsc,server \"tsc --watch --preserveWatchOutput --outDir \"build/src\" --declarationDir \"build/declarations\"\" \"http-server ./ -s -o /tests/playground.html -c-1\"",
     "tsc": "gulp tsc",
     "test": "gulp test",
@@ -50,7 +48,8 @@
     "test:generators": "gulp testGenerators",
     "test:mocha:interactive": "npm run build && concurrently -n tsc,server \"tsc --watch --preserveWatchOutput --outDir \"build/src\" --declarationDir \"build/declarations\"\" \"gulp interactiveMocha\"",
     "test:compile:advanced": "gulp buildAdvancedCompilationTest --debug",
-    "updateGithubPages": "npm ci && gulp gitUpdateGithubPages"
+    "updateGithubPages": "npm ci && gulp updateGithubPages --upstream",
+    "updateGithubPages:staging": "npm ci && gulp updateGithubPages --use-local"
   },
   "exports": {
     ".": {
@@ -114,6 +113,8 @@
     "async-done": "^2.0.0",
     "chai": "^6.0.1",
     "concurrently": "^9.0.1",
+    "conventional-changelog-conventionalcommits": "^7.0.2",
+    "conventional-recommended-bump": "^9.0.0",
     "eslint": "^9.15.0",
     "eslint-config-google": "^0.14.0",
     "eslint-config-prettier": "^10.1.1",
@@ -122,16 +123,13 @@
     "eslint-plugin-prettier": "^5.2.1",
     "glob": "^11.0.1",
     "globals": "^16.0.0",
-    "google-closure-compiler": "^20260315.0.0",
+    "google-closure-compiler": "^20260330.0.0",
     "gulp": "^5.0.0",
     "gulp-concat": "^2.6.1",
     "gulp-gzip": "^1.4.2",
     "gulp-header": "^2.0.9",
-    "gulp-insert": "^0.5.0",
     "gulp-rename": "^2.0.0",
     "gulp-replace": "^1.0.0",
-    "gulp-series": "^1.0.2",
-    "gulp-shell": "^0.8.0",
     "gulp-sourcemaps": "^3.0.0",
     "gulp-umd": "^2.0.0",
     "http-server": "^14.0.0",
diff --git a/packages/blockly/scripts/gulpfiles/git_tasks.mjs b/packages/blockly/scripts/gulpfiles/git_tasks.mjs
index 2b08e16b3..6a68b54be 100644
--- a/packages/blockly/scripts/gulpfiles/git_tasks.mjs
+++ b/packages/blockly/scripts/gulpfiles/git_tasks.mjs
@@ -8,17 +8,36 @@
  * @fileoverview Git-related gulp tasks for Blockly.
  */
 
+
 import * as gulp from 'gulp';
 import {execSync} from 'child_process';
+import yargs from 'yargs';
+import { hideBin } from 'yargs/helpers';
 
 import * as buildTasks from './build_tasks.mjs';
 import * as packageTasks from './package_tasks.mjs';
 
-const UPSTREAM_URL = 'https://github.com/google/blockly.git';
+const UPSTREAM_URL = 'git@github.com:RaspberryPiFoundation/blockly.git';
+
+// Use yargs to parse --remote argument
+const argv = yargs(hideBin(process.argv)).option('remote', {
+    type: 'string',
+    describe: 'Remote to push gh-pages to',
+    demandOption: false
+}).option('upstream', {
+  type: 'boolean',
+  describe: 'Push to RaspberryPiFoundation/blockly instead of origin',
+  demandOption: false
+}).option('use-local', {
+  type: 'boolean',
+  describe: 'Build and push from current branch instead of syncing with main',
+  demandOption: false
+}).help().argv;
+const remoteToUse = argv.upstream ? UPSTREAM_URL : resolveRemote(argv.remote);
 
 /**
  * Extra paths to include in the gh_pages branch (beyond the normal
- * contents of master / develop).  Passed to shell unquoted, so can
+ * contents of main).  Passed to shell unquoted, so can
  * include globs.
  */
 const EXTRAS = [
@@ -28,140 +47,122 @@ const EXTRAS = [
   'build/*.loader.mjs',
 ];
 
-let upstream = null;
-
 /**
- * Get name of git remote for upstream (typically 'upstream', but this
- * is just convention and can be changed.)
- */
-function getUpstream() {
-  if (upstream) return upstream;
-  for (const line of String(execSync('git remote -v')).split('\n')) {
-    if (line.includes('google/blockly')) {
-      upstream = line.split('\t')[0];
-      return upstream;
-    }
-  }
-  throw new Error('Unable to determine upstream URL');
-}
-
-/**
- * Stash current state, check out the named branch, and sync with
- * google/blockly.
+ * Stash current state, check out the named branch, and pull
+ * changes from RaspberryPiFoundation/blockly.
  */
 function syncBranch(branchName) {
   return function(done) {
     execSync('git stash save -m "Stash for sync"', { stdio: 'inherit' });
     checkoutBranch(branchName);
     execSync(`git pull ${UPSTREAM_URL} ${branchName}`, { stdio: 'inherit' });
-    execSync(`git push origin ${branchName}`, { stdio: 'inherit' });
     done();
   };
 }
 
 /**
- * Stash current state, check out develop, and sync with
- * google/blockly.
+ * Stash current state, check out main, and sync with
+ * RaspberryPiFoundation/blockly.
  */
-export function syncDevelop() {
-  return syncBranch('develop');
+export function syncMain() {
+  return syncBranch('main');
 };
 
 /**
- * Stash current state, check out master, and sync with
- * google/blockly.
- */
-export function syncMaster() {
-  return syncBranch('master');
-};
-
-/**
- * Helper function: get a name for a rebuild branch. Format:
- * rebuild_mm_dd_yyyy.
- */
-function getRebuildBranchName() {
-  const date = new Date();
-  const mm = date.getMonth() + 1;  // Month, 0-11
-  const dd = date.getDate();  // Day of the month, 1-31
-  const yyyy = date.getFullYear();
-  return `rebuild_${mm}_${dd}_${yyyy}`;
-};
-
-/**
- * Helper function: get a name for a rebuild branch. Format:
- * rebuild_yyyy_mm.
- */
-function getRCBranchName() {
-  const date = new Date();
-  const mm = date.getMonth() + 1;  // Month, 0-11
-  const yyyy = date.getFullYear();
-  return `rc_${yyyy}_${mm}`;
-};
-
-/**
- * If branch does not exist then create the branch.
  * If branch exists switch to branch.
+ * If branch does not exist then create the branch.
  */
 function checkoutBranch(branchName) {
-  execSync(`git switch -c ${branchName}`,
+  execSync(`git switch ${branchName} || git switch -c ${branchName}`,
       { stdio: 'inherit' });
 }
 
 /**
- * Create and push an RC branch.
- * Note that this pushes to google/blockly.
- */
-export const createRC = gulp.series(
-  syncDevelop(),
-  function(done) {
-    const branchName = getRCBranchName();
-    execSync(`git switch -C ${branchName}`, { stdio: 'inherit' });
-    execSync(`git push ${UPSTREAM_URL} ${branchName}`, { stdio: 'inherit' });
-    done();
-  }
-);
-
-/** Create the rebuild branch. */
-export function createRebuildBranch(done) {
-  const branchName = getRebuildBranchName();
-  console.log(`make-rebuild-branch: creating branch ${branchName}`);
-  execSync(`git switch -C ${branchName}`, { stdio: 'inherit' });
-  done();
-}
-
-/** Push the rebuild branch to origin. */
-export function pushRebuildBranch(done) {
-  console.log('push-rebuild-branch: committing rebuild');
-  execSync('git commit -am "Rebuild"', { stdio: 'inherit' });
-  const branchName = getRebuildBranchName();
-  execSync(`git push origin ${branchName}`, { stdio: 'inherit' });
-  console.log(`Branch ${branchName} pushed to GitHub.`);
-  console.log('Next step: create a pull request against develop.');
-  done();
-}
-
-/**
- * Update github pages with what is currently in develop.
+ * Update github pages with what is currently in main (or current branch if --use-local).
  *
  * Prerequisites (invoked): clean, build.
+ *
+ * Usage:
+ *   gulp updateGithubPages # sync main, then use origin if exists
+ *   gulp updateGithubPages --upstream # uses hardcoded upstream
+ *   gulp updateGithubPages --remote <remote> # uses named remote
+ *   gulp updateGithubPages --use-local # build from current branch, skip syncing main
+ *
  */
 export const updateGithubPages = gulp.series(
-  function(done) {
-    execSync('git stash save -m "Stash for sync"', { stdio: 'inherit' });
-    execSync('git switch -C gh-pages', { stdio: 'inherit' });
-    execSync(`git fetch ${getUpstream()}`, { stdio: 'inherit' });
-    execSync(`git reset --hard ${getUpstream()}/develop`, { stdio: 'inherit' });
-    done();
-  },
-  buildTasks.cleanBuildDir,
-  packageTasks.cleanReleaseDir,
-  buildTasks.build,
-  function(done) {
-    // Extra paths (e.g. build/, dist/ etc.) are normally gitignored,
-    // so we have to force add.
-    execSync(`git add -f ${EXTRAS.join(' ')}`, {stdio: 'inherit'});
-    execSync('git commit -am "Rebuild"', {stdio: 'inherit'});
-    execSync(`git push ${UPSTREAM_URL} gh-pages --force`, {stdio: 'inherit'});
-    done();
+    function (done) {
+        if (!remoteToUse) {
+          const attemptedRemote = argv.remote || 'origin';
+          const remoteLabel = argv.remote
+            ? `Remote '${attemptedRemote}'`
+            : "Remote 'origin' (default)";
+          const errMsg = `${remoteLabel} not found in git remotes. ` +
+            'Please add that remote or use --upstream.\n' +
+            'Usage: gulp updateGithubPages [--remote <remote> | --upstream]';
+          console.error(errMsg);
+          done(new Error(errMsg));
+          return;
+        }
+        done();
+    },
+    function (done) {
+      if (!argv.useLocal) {
+        done();
+        return;
+      }
+      const status = execSync('git status --porcelain', { encoding: 'utf8' });
+      if (status.trim()) {
+        const errMsg =
+          'You cannot push the local branch with uncommitted changes. ' +
+          'Please commit or stash your changes first.';
+        console.error(errMsg);
+        done(new Error(errMsg));
+        return;
+      }
+      done();
+    },
+    function (done) {
+      if (argv.useLocal) {
+        done();
+        return;
+      }
+      syncMain()(done);
+    },
+    function(done) {
+      const sourceRef = argv.useLocal
+        ? execSync('git rev-parse HEAD', { encoding: 'utf8' }).trim()
+        : 'main';
+      execSync('git switch -C gh-pages', { stdio: 'inherit' });
+      execSync(`git reset --hard ${sourceRef}`, { stdio: 'inherit' });
+      done();
+    },
+    buildTasks.cleanBuildDir,
+    packageTasks.cleanReleaseDir,
+    buildTasks.build,
+    function(done) {
+      // Extra paths (e.g. build/, dist/ etc.) are normally gitignored,
+      // so we have to force add.
+      execSync(`git add -f ${EXTRAS.join(' ')}`, {stdio: 'inherit'});
+      execSync('git commit -am "Rebuild"', {stdio: 'inherit'});
+      execSync(`git push ${remoteToUse} gh-pages --force`, {stdio: 'inherit'});
+      done();
+    }
+  );
+
+/**
+ * Resolves which remote to use for pushing gh-pages.
+ * @param {string} remoteArg
+ * @returns {string|undefined} The remote name, or undefined if not found.
+ */
+function resolveRemote(remoteArg) {
+  const remoteName = remoteArg || 'origin';
+  try {
+    const remotes = execSync('git remote', {encoding: 'utf8'}).split(/\r?\n/).map(r => r.trim()).filter(Boolean);
+    if (remotes.includes(remoteName)) {
+      return remoteName;
+    }
+    return undefined;
+  } catch (e) {
+    return undefined;
   }
-);
+}
diff --git a/packages/blockly/scripts/gulpfiles/release_tasks.mjs b/packages/blockly/scripts/gulpfiles/release_tasks.mjs
index a678a4f24..ca9c9ffa1 100644
--- a/packages/blockly/scripts/gulpfiles/release_tasks.mjs
+++ b/packages/blockly/scripts/gulpfiles/release_tasks.mjs
@@ -18,55 +18,6 @@ import * as packageTasks from './package_tasks.mjs';
 import {getPackageJson} from './helper_tasks.mjs';
 import {RELEASE_DIR} from './config.mjs';
 
-
-// Gets the current major version.
-function getMajorVersion() {
-  const { version } = getPackageJson();
-  const re = new RegExp(/^(\d)./);
-  const match = re.exec(version);
-  if (!match[0]) {
-    return null;
-  }
-  console.log(match[0]);
-  return parseInt(match[0]);
-}
-
-// Updates the version depending on user input.
-function updateVersion(done, updateType) {
-  const majorVersion = getMajorVersion();
-  if (!majorVersion) {
-    done(new Error('Something went wrong when getting the major version number.'));
-  } else if (!updateType) {
-    // User selected to cancel.
-    done(new Error('Cancelling process.'));
-  }
-
-  switch (updateType.toLowerCase()) {
-    case 'major':
-      majorVersion++;
-      execSync(`npm --no-git-tag-version version ${majorVersion}.$(date +'%Y%m%d').0`, {stdio: 'inherit'});
-      done();
-      break;
-    case 'minor':
-      execSync(`npm --no-git-tag-version version ${majorVersion}.$(date +'%Y%m%d').0`, {stdio: 'inherit'});
-      done();
-      break;
-    case 'patch':
-      execSync(`npm --no-git-tag-version version patch`, {stdio: 'inherit'});
-      done();
-      break;
-    default:
-      done(new Error('Unexpected update type was chosen.'))
-  }
-}
-
-// Prompt the user to figure out what kind of version update we should do.
-function updateVersionPrompt(done) {
-  const releaseTypes = ['Major', 'Minor', 'Patch'];
-  const index = readlineSync.keyInSelect(releaseTypes, 'Which version type?');
-  updateVersion(done, releaseTypes[index]);
-}
-
 // Checks with the user that they are on the correct git branch.
 function checkBranch(done) {
   const gitBranchName = execSync('git rev-parse --abbrev-ref HEAD').toString();
@@ -162,13 +113,3 @@ export const publishBeta = gulp.series(
   checkReleaseDir,
   loginAndPublishBeta
 );
-
-// Switch to a new branch, update the version number, build Blockly
-// and check in the resulting built files.
-export const recompile = gulp.series(
-  gitTasks.syncDevelop(),
-  gitTasks.createRebuildBranch,
-  updateVersionPrompt,
-  packageTasks.pack,  // Does clean + build.
-  gitTasks.pushRebuildBranch
-  );