Rebase on upstream 4.3.2 to support ESR 115+128 - happy to help

With a new ESR release coming up, it would be great to have a working config packaged in Purism. 4.2.0 has been broken with 115 already, and it would be great to fix this.

Upstream 4.3.2 (https://gitlab.com/postmarketOS/mobile-config-firefox/-/tags/4.3.2) has been confirmed to work with current Firefox nightly 129a, so 128 should be all fine.

I'll look into rebasing the current patchset to the new upstream release, but given the MR !6 (merged) that (would have changed behavior, but helped users anyway, as it's a working config) has not been merged, I'd appreciate a short comment by @sebastian.krzyszkowiak or someone else with merge rights, that I am not spending my time without it then having the desired outcome.