Puppeteer "Could not find Chromium (rev. X)" in CI

Puppeteer could not locate the Chromium build it expects. Either the post-install download was skipped, or the browser was installed to a cache directory that does not match where the launch looks at runtime.

What this error means

The launch throws "Could not find Chromium (rev. 1108766)" on older Puppeteer, or "Could not find expected browser (chrome) locally. Run npm install to download the correct Chromium revision" on newer versions.

Puppeteer

Error: Could not find expected browser (chrome) locally. Expected to find the browser
at /home/runner/.cache/puppeteer/chrome/linux-124.0.6367.60/chrome-linux64/chrome
Run 'npm install' or 'npx puppeteer browsers install chrome' to download the browser.

Common causes

The Chromium download was skipped at install

A PUPPETEER_SKIP_DOWNLOAD flag or a network failure during npm install left no browser on disk, so the launch has nothing to run.

The browser is in a different cache directory

The install wrote to one PUPPETEER_CACHE_DIR, but the launch resolves a different default path, so it reports the browser as missing.

How to fix it

Install the browser explicitly

Ensure the download is not skipped for the install step.
Run the Puppeteer browsers installer after npm ci.
Confirm the launch uses the same cache directory the install wrote to.

Terminal

npm ci
npx puppeteer browsers install chrome

Pin one cache directory

Set PUPPETEER_CACHE_DIR at job level so install and launch resolve the same path.

.github/workflows/ci.yml

env:
  PUPPETEER_CACHE_DIR: ${{ github.workspace }}/.puppeteer

How to prevent it

Run npx puppeteer browsers install chrome in CI after installing modules.
Set PUPPETEER_CACHE_DIR consistently across install, cache, and test steps.
Do not set skip-download unless you provide an external Chrome.