playwright firefox and webkit fail in docker: missing dependencies

TL;DR

Install the OS-level browser dependencies inside the image with npx playwright install --with-deps (it needs apt access at build time). The quickest reliable fix is basing your image on the official Playwright Docker image, which ships every dependency for Chromium, Firefox, and WebKit. Missing system libraries are the cause whenever Chromium works but Firefox and WebKit crash on launch.

Error

browserType.launch: Host system is missing dependencies to run browsers.
Please install them with the following command:
  sudo npx playwright install-deps firefox

Steps

1. In your Dockerfile, run the install as root before dropping privileges: RUN npx playwright install --with-deps. Expected: the build log shows apt installing the browser dependency packages.
2. Or switch the base image to the official one, for example FROM mcr.microsoft.com/playwright:v1.49.1-jammy. Expected: the image build succeeds with all browser deps present.
3. Re-run the failing Firefox and WebKit tests in the rebuilt image. Expected: both browsers launch and the tests execute.

When to use

• Firefox or WebKit fail at launch inside Docker while Chromium works.
• The error mentions missing dependencies or missing shared libraries.
• You are on a slim base image like node:slim.

When not to use

• The browser binaries themselves failed to download (run npx playwright install first).
• The container cannot reach the network through a proxy.
• You need headed mode with a display (that needs xvfb, a different setup).

Tool compatibility

• Playwright 1.40 through 1.5x; match the Docker image tag to your Playwright version.
• Debian-based images (-jammy); --with-deps uses apt, so it does not apply to Alpine.

Variant phrasings

playwright firefox failed to launch in docker container

Same missing-libraries root cause; install the deps or use the official image.

webkit launch failed missing shared libraries docker

The missing .so errors are the same dependency gap.

Why it happens

Playwright downloads browser binaries with install, but Firefox and WebKit need many more system shared libraries than Chromium does. Slim base images lack them, so the browser process dies at launch while Chromium (with fewer deps) survives.

Edge cases

• Corporate proxy blocks apt: pre-bake the deps into a base image once instead of installing per build.
• --with-deps needs root: run it in a root build stage, then copy to the runtime user.
• Still fails after deps: check shared memory (--shm-size=1gb or mount /dev/shm); low shm usually crashes Chromium first, but it can bite the others too.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_d2MyP6Pz9IZfKOcOj1jp3w