diff --git a/.github/workflows/rainforestqa.yml b/.github/workflows/rainforestqa.yml
index 58772179f2..2ac758a202 100644
--- a/.github/workflows/rainforestqa.yml
+++ b/.github/workflows/rainforestqa.yml
@@ -29,8 +29,7 @@ jobs:
       # The following environment variables are set so sourceMapPublicUrl, and there SOURCE_MAP_PUBLIC_PATH, is defined in the build
       PUBLIC_RELEASE: true
       SOURCE_MAP_URL_BASE: https://pixiebrix-extension-source-maps.s3.amazonaws.com
-      # Use mv2 because that's currently what the Rainforest build uses, see "npm run build" step below
-      SOURCE_MAP_PATH: sourcemaps/build/${{ github.sha }}/mv2
+      SOURCE_MAP_PATH: sourcemaps/build/${{ github.sha }}/mv3
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
@@ -41,7 +40,7 @@ jobs:
       - run: npm ci
       - run: npm run build
         env:
-          MV: 2
+          MV: 3
           DATADOG_CLIENT_TOKEN: ${{ secrets.DATADOG_CLIENT_TOKEN }}
           DATADOG_APPLICATION_ID: ${{ secrets.DATADOG_APPLICATION_ID }}
           CHROME_MANIFEST_KEY: ${{ secrets.CHROME_MANIFEST_PROD_PUBLIC_KEY }}