diff --git a/.github/actions/setup-electron/action.yml b/.github/actions/setup-electron/action.yml
new file mode 100644
index 000000000000..2aaef4c1b082
--- /dev/null
+++ b/.github/actions/setup-electron/action.yml
@@ -0,0 +1,98 @@
+name: Setup Electron
+description: Restores cached Electron archives, validates and prepares Electron, and optionally saves the cache.
+
+inputs:
+  arch:
+    description: Target Electron architecture.
+    required: true
+  lookup-only:
+    description: When 'true', only checks whether the cache entry exists without restoring archives or preparing Electron.
+    default: 'false'
+  save-cache:
+    description: When 'true', saves the archives after successful setup on a cache miss. Ignored when lookup-only is 'true'.
+    default: 'false'
+
+outputs:
+  cache-hit:
+    description: "'true' when an exact Electron cache key match was found."
+    value: ${{ steps.restore.outputs.cache-hit }}
+
+runs:
+  using: composite
+  steps:
+    - name: Prepare Electron cache path
+      if: runner.os != 'Windows'
+      shell: bash
+      run: |
+        if [ "$RUNNER_OS" = "macOS" ]; then
+          echo "ELECTRON_CACHE_PATH=$HOME/Library/Caches/electron" >> "$GITHUB_ENV"
+        else
+          echo "ELECTRON_CACHE_PATH=${XDG_CACHE_HOME:-$HOME/.cache}/electron" >> "$GITHUB_ENV"
+        fi
+
+    - name: Prepare Electron cache path
+      if: runner.os == 'Windows'
+      shell: pwsh
+      run: |
+        $cacheRoot = if ($env:LOCALAPPDATA) { $env:LOCALAPPDATA } else { Join-Path $HOME 'AppData/Local' }
+        Add-Content -Path $env:GITHUB_ENV -Value "ELECTRON_CACHE_PATH=$(Join-Path $cacheRoot 'electron/Cache')"
+
+    - name: Restore Electron cache
+      id: restore
+      uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      with:
+        path: ${{ env.ELECTRON_CACHE_PATH }}
+        key: "electron-download-v1-${{ runner.os }}-${{ inputs.arch }}-${{ hashFiles('.npmrc', 'build/checksums/electron.txt') }}"
+        lookup-only: ${{ inputs.lookup-only }}
+
+    - name: Download Electron
+      if: inputs.lookup-only != 'true' && runner.os != 'Windows'
+      shell: bash
+      run: |
+        for i in {1..3}; do
+          if npm run electron -- "$VSCODE_ARCH"; then
+            echo "Download successful on attempt $i"
+            break
+          fi
+
+          if [ $i -eq 3 ]; then
+            echo "Download failed after 3 attempts" >&2
+            exit 1
+          fi
+
+          echo "Download failed on attempt $i, retrying..."
+          sleep 5
+        done
+      env:
+        VSCODE_ARCH: ${{ inputs.arch }}
+
+    - name: Download Electron
+      if: inputs.lookup-only != 'true' && runner.os == 'Windows'
+      shell: pwsh
+      run: |
+        . build/azure-pipelines/win32/exec.ps1
+        $ErrorActionPreference = "Stop"
+
+        for ($i = 1; $i -le 3; $i++) {
+          try {
+            exec { npm run electron -- $env:VSCODE_ARCH }
+            break
+          }
+          catch {
+            if ($i -eq 3) {
+              Write-Error "Download failed after 3 attempts"
+              throw
+            }
+            Write-Host "Download failed attempt $i, retrying..."
+            Start-Sleep -Seconds 2
+          }
+        }
+      env:
+        VSCODE_ARCH: ${{ inputs.arch }}
+
+    - name: Save Electron cache
+      if: inputs.lookup-only != 'true' && inputs.save-cache == 'true' && steps.restore.outputs.cache-hit != 'true'
+      uses: actions/cache/save@caa296126883cff596d87d8935842f9db880ef25 # v5.1.0
+      with:
+        path: ${{ env.ELECTRON_CACHE_PATH }}
+        key: ${{ steps.restore.outputs.cache-primary-key }}
diff --git a/.github/workflows/node_modules_cache/README.md b/.github/workflows/node_modules_cache/README.md
index 00ea96811192..5ebb82c00afc 100644
--- a/.github/workflows/node_modules_cache/README.md
+++ b/.github/workflows/node_modules_cache/README.md
@@ -33,3 +33,39 @@ Example usage from a workflow step:
 If you change the archive format or flags, update both the `archive` and
 `extract` branch of the script, and bump `build/.cachesalt` to invalidate
 existing caches.
+
+## Electron download cache
+
+The platform jobs in [pr-node-modules.yml](../pr-node-modules.yml) also warm a
+separate Electron download cache on `main`. The
+[setup-electron](../../actions/setup-electron/action.yml) action shares cache
+handling and download retries with the Linux, macOS, and Windows PR test
+workflows:
+
+- By default, restore cached archives and validate/prepare Electron, downloading
+  with up to three attempts as needed. PR jobs use this mode without saving.
+- `lookup-only: 'true'` only checks for a cache entry, without restoring archives,
+  preparing Electron, or saving. This mode does not require npm dependencies.
+- `save-cache: 'true'` also saves after successful setup on a cache miss.
+
+The cache stores `@electron/get`'s original download archives, not the prepared
+`.build/electron` application. Its key includes the runner OS, target
+architecture, and a hash of `.npmrc` and `build/checksums/electron.txt`. Ordinary
+`package-lock.json` changes do not invalidate it. If a downloader update changes
+the cache format, bump the `electron-download-v1` prefix in `setup-electron`.
+
+The paths match `@electron/get`'s platform defaults, including `XDG_CACHE_HOME`
+on Linux and `LOCALAPPDATA` on Windows. Cache paths and keys are handled within
+the action.
+
+Even on a cache hit, PR jobs run `npm run electron` to validate and prepare the
+application from the cached archives using the current checkout. Checksum
+validation remains enabled: the current downloader still fetches
+`SHASUMS256.txt` from GitHub, so this cache avoids the large ZIP downloads but
+does not make Electron setup entirely network-independent.
+
+On `main`, an Electron cache hit uses lookup-only checks and skips downloading
+Electron. On a miss, the platform job restores `node_modules` (or installs them
+if that cache also misses), then invokes `setup-electron` with `save-cache: 'true'`.
+This checks the cache again before preparing and saving Electron, while keeping
+already-warm jobs from extracting dependency archives unnecessarily.
diff --git a/.github/workflows/pr-darwin-test.yml b/.github/workflows/pr-darwin-test.yml
index 3fc4fbea2e97..88aa192d0352 100644
--- a/.github/workflows/pr-darwin-test.yml
+++ b/.github/workflows/pr-darwin-test.yml
@@ -108,25 +108,11 @@ jobs:
       - name: Transpile client and extensions
         run: npm run gulp transpile-client-esbuild transpile-extensions
 
-      - name: Download Electron
+      - name: Setup Electron
         if: ${{ inputs.electron_tests || inputs.remote_tests }}
-        run: |
-          set -e
-
-          for i in {1..3}; do # try 3 times (matching retryCountOnTaskFailure: 3)
-            if npm run electron -- ${{ env.VSCODE_ARCH }}; then
-              echo "Download successful on attempt $i"
-              break
-            fi
-
-            if [ $i -eq 3 ]; then
-              echo "Download failed after 3 attempts" >&2
-              exit 1
-            fi
-
-            echo "Download failed on attempt $i, retrying..."
-            sleep 5 # optional: add a small delay between retries
-          done
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/.github/workflows/pr-linux-test.yml b/.github/workflows/pr-linux-test.yml
index 057fb511a3f7..fd2112ff320f 100644
--- a/.github/workflows/pr-linux-test.yml
+++ b/.github/workflows/pr-linux-test.yml
@@ -308,25 +308,11 @@ jobs:
       - name: Transpile client and extensions
         run: npm run gulp transpile-client-esbuild transpile-extensions
 
-      - name: Download Electron
+      - name: Setup Electron
         if: ${{ inputs.electron_tests || inputs.remote_tests }}
-        run: |
-          set -e
-
-          for i in {1..3}; do # try 3 times (matching retryCountOnTaskFailure: 3)
-            if npm run electron -- ${{ env.VSCODE_ARCH }}; then
-              echo "Download successful on attempt $i"
-              break
-            fi
-
-            if [ $i -eq 3 ]; then
-              echo "Download failed after 3 attempts" >&2
-              exit 1
-            fi
-
-            echo "Download failed on attempt $i, retrying..."
-            sleep 5 # optional: add a small delay between retries
-          done
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/.github/workflows/pr-node-modules.yml b/.github/workflows/pr-node-modules.yml
index 8b83a03492fe..89f1b2377c73 100644
--- a/.github/workflows/pr-node-modules.yml
+++ b/.github/workflows/pr-node-modules.yml
@@ -88,13 +88,20 @@ jobs:
         with:
           node-version-file: .nvmrc
 
+      - name: Check Electron cache
+        id: cache-electron
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          lookup-only: 'true'
+
       - name: Restore node_modules cache
         id: cache-node-modules
         uses: ./.github/actions/restore-node-modules
         with:
           key-prefix: node_modules-linux
           key-args: "linux ${{ env.VSCODE_ARCH }} $(node -p process.arch)"
-          lookup-only: 'true'
+          lookup-only: ${{ steps.cache-electron.outputs.cache-hit == 'true' }}
 
       - name: Install build dependencies
         if: steps.cache-node-modules.outputs.cache-hit != 'true'
@@ -143,6 +150,15 @@ jobs:
         if: steps.cache-node-modules.outputs.cache-hit != 'true'
         uses: ./.github/actions/save-node-modules
 
+      - name: Setup Electron
+        if: steps.cache-electron.outputs.cache-hit != 'true'
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          save-cache: 'true'
+        env:
+          GITHUB_TOKEN: ${{ secrets.VSCODE_OSS }}
+
   macOS:
     name: macOS
     runs-on: macos-26-xlarge
@@ -158,13 +174,20 @@ jobs:
         with:
           node-version-file: .nvmrc
 
+      - name: Check Electron cache
+        id: cache-electron
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          lookup-only: 'true'
+
       - name: Restore node_modules cache
         id: cache-node-modules
         uses: ./.github/actions/restore-node-modules
         with:
           key-prefix: node_modules-macos
           key-args: "darwin ${{ env.VSCODE_ARCH }} $(node -p process.arch)"
-          lookup-only: 'true'
+          lookup-only: ${{ steps.cache-electron.outputs.cache-hit == 'true' }}
 
       - name: Install dependencies
         if: steps.cache-node-modules.outputs.cache-hit != 'true'
@@ -202,6 +225,15 @@ jobs:
         if: steps.cache-node-modules.outputs.cache-hit != 'true'
         uses: ./.github/actions/save-node-modules
 
+      - name: Setup Electron
+        if: steps.cache-electron.outputs.cache-hit != 'true'
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          save-cache: 'true'
+        env:
+          GITHUB_TOKEN: ${{ secrets.VSCODE_OSS }}
+
   windows:
     name: Windows
     runs-on: [ self-hosted, 1ES.Pool=1es-vscode-oss-windows-2022-x64, "JobId=windows-${{ github.run_id }}-${{ github.run_number }}-${{ github.run_attempt }}" ]
@@ -217,13 +249,20 @@ jobs:
         with:
           node-version-file: .nvmrc
 
+      - name: Check Electron cache
+        id: cache-electron
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          lookup-only: 'true'
+
       - name: Restore node_modules cache
         id: node-modules-cache
         uses: ./.github/actions/restore-node-modules
         with:
           key-prefix: node_modules-windows
           key-args: "win32 ${{ env.VSCODE_ARCH }} $(node -p process.arch)"
-          lookup-only: 'true'
+          lookup-only: ${{ steps.cache-electron.outputs.cache-hit == 'true' }}
 
       - name: Install dependencies
         if: steps.node-modules-cache.outputs.cache-hit != 'true'
@@ -261,6 +300,15 @@ jobs:
         if: steps.node-modules-cache.outputs.cache-hit != 'true'
         uses: ./.github/actions/save-node-modules
 
+      - name: Setup Electron
+        if: steps.cache-electron.outputs.cache-hit != 'true'
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
+          save-cache: 'true'
+        env:
+          GITHUB_TOKEN: ${{ secrets.VSCODE_OSS }}
+
   copilot-linux:
     name: Copilot (Linux)
     runs-on: [ self-hosted, 1ES.Pool=1es-vscode-oss-ubuntu-22.04-x64, "JobId=copilot-linux-${{ github.run_id }}-${{ github.run_number }}-${{ github.run_attempt }}" ]
diff --git a/.github/workflows/pr-win32-test.yml b/.github/workflows/pr-win32-test.yml
index 8680fae6cf28..576575957ffe 100644
--- a/.github/workflows/pr-win32-test.yml
+++ b/.github/workflows/pr-win32-test.yml
@@ -116,27 +116,11 @@ jobs:
         shell: pwsh
         run: npm run gulp "transpile-client-esbuild" "transpile-extensions"
 
-      - name: Download Electron
+      - name: Setup Electron
         if: ${{ inputs.electron_tests || inputs.remote_tests }}
-        shell: pwsh
-        run: |
-          . build/azure-pipelines/win32/exec.ps1
-          $ErrorActionPreference = "Stop"
-
-          for ($i = 1; $i -le 3; $i++) {
-            try {
-              exec { npm run electron -- ${{ env.VSCODE_ARCH }} }
-              break
-            }
-            catch {
-              if ($i -eq 3) {
-                Write-Error "Download failed after 3 attempts"
-                throw
-              }
-              Write-Host "Download failed attempt $i, retrying..."
-              Start-Sleep -Seconds 2
-            }
-          }
+        uses: ./.github/actions/setup-electron
+        with:
+          arch: ${{ env.VSCODE_ARCH }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}