This branch contains modifications to the mozilla:release branch for compiling the Record Replay gecko based browser.

Getting started:

macOS

1. Make sure that you are using Python v2.7
2. cp mozconfig.macsample mozconfig
3. Download MacOSX11.1.sdk.tar.xz from https://github.com/phracker/MacOSX-SDKs/releases
4. untar MacOSX11.1.sdk.tar.xz in the repo root to create a MacOSX11.1.sdk directory
5. run ./mach bootstrap and select (2) Firefox Desktop
6. run node build
   • On Apple Silicon, you many need to run RUSTC_BOOTSTRAP=qcms node build to build successfully.
7. run ./mach run

Linux

1. cp mozconfig.linuxsample mozconfig
2. run ./mach bootstrap and select (2) Firefox Desktop
3. run node build
4. run ./mach run

Troubleshooting Tips

• If you change your PATH to point to a different version of say Python or Rust you need to rerun ./mach bootstrap to get the build system to pick up the change.

Merging from upstream

1. Checkout the release branch, pull from upstream release branch:

git checkout release
git pull https://github.com/mozilla/gecko-dev.git release

2. Switch to a new branch, merge from the release branch.

git checkout webreplay-release
git checkout -b replay-merge
git merge release

3. Fix merge conflicts.
4. Fix build breaks.
5. Make sure the output binary is replay and not firefox.
6. Get e2e tests etc. to pass.
7. At this point it is reasonably safe to merge into the webreplay-release branch.

git checkout webreplay-release
git merge replay-merge
git push

8. Update geckoVersion in the backend.
9. Make sure automatic updates work with the new browser. Deploy a browser but do not release it, then open it, open "About Replay" and see if it updates.

Tips for debugging:

• Look at the update server logs to make sure requests are being processed correctly.
• Set the app.update.log browser config when running, and then check console output.
• If there is a line like *** AUS:SVC readStatusFile - status: failed: 23, path: /path/to/update.status, this is produced by the C++ updater which can be found in UpdateThreadFunc in updater.cpp. Building a local browser with instrumentation is likely needed to investigate.

10. Run live test harness and make sure crash rate is acceptable.

Miscelleneous

Speeding up oh-my-zsh

git config --add oh-my-zsh.hide-status 1
git config --add oh-my-zsh.hide-dirty 1