Bug 40811: Make it easier to test the updater

Merge Info

Related Issues

• #40811 (closed)
• etc

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

With these changes, it is possible to set a URL for the browser to check updates.

When it is set, a marsigner.der is passed to the container, to replace the official nightly keys.

It does not do other stuff, such as using custom URLs to generate the update responses, nor allow signing automatically MARs.

It would be handy, too, but I don't have a clue on how to modify the perl scripts.