Quick start guide misses troubleshooting for Apple Silicon package resolution and broken CSS

[bobcorn]

What

• During local setup with the Docker quick start, two troubleshooting cases were not easy to find in the main guide.
• On Apple Silicon (arm64), make dev can fail during image build with errors like E: Unable to locate package libzxing-dev.
• After containers are running, pages can load without styles because the generated stylesheet URL can become app-.css (missing ltr/rtl).

Steps to reproduce the behavior

1. On Apple Silicon (arm64), follow the quick start and run make dev.
2. Observe build failure with E: Unable to locate package libzxing-dev.
3. Start the stack (after fixing the previous issue) and open http://world.openfoodfacts.localhost.
4. Inspect HTML and see stylesheet link like .../css/dist/app-.css?..., with broken styling.

Expected behavior

• Troubleshooting includes an Apple Silicon workaround for missing amd64-only packages.
• Troubleshooting includes a recovery path when CSS is broken due to app-.css.

Why

• Adding these two entries would make onboarding smoother for new contributors.
• This was identified while following the quick start end-to-end.
• It aligns with the project’s invitation to improve documentation.

Additional context

• Effective local recovery commands:
  • Apple Silicon:

    DOCKER_DEFAULT_PLATFORM=linux/amd64 make dev
    

  • Broken CSS:

    make build_lang
    docker compose restart backend frontend dynamicfront
    

    Then force-reload the page (or clear browser cache).

Platform

• Operating System: macOS 26.4 Beta (25E5207k) on Apple Silicon (arm64)
• Docker Desktop: 4.61.0 (219004)
• Browser: Safari 26.4 Beta (25E5207k)