Rebase and Release-Prep for Mullvad Browser 12.0a4

Merge Info

Related Issues

• #101 (closed)

Backport Timeline

• Immediate - patchsets for critical bug fixes or other major blocker (e.g. fixes for a 0-day exploit) OR patchsets with trivial changes which do not need testing (e.g. fixes for typos or fixes easily verified in a local developer build)
• Next Minor Stable Release - patchset that needs to be verified in nightly before backport
• Eventually - patchset that needs to be verified in alpha before backport
• No Backport - patchset for the next major stable

Issue Tracking

• Link resolved issues with appropriate Release Prep issue for changelog generation

Change Description

Rebased onto current base-browser with the browser-colors.css changes ( so fixes https://gitlab.torproject.org/tpo/applications/privacy-browser/-/issues/99 ) and organized the patches a bit. A git diff richard/bug_101 origin-push/privacy-browser-102.8.0esr-12.0-1 gives only the base-browser colors.css changes.

/cc @ma1