MB 140: Prepare Mullvad Browser Release 12.0a9

Merge Info

Related Issues

• privacy-browser#140

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

One more build with the right channel and update responses path to verify MAR updater.