Add Betterbird to repos

[timur-g]

I use Mint 21.3 and could find various PPAs or DEBs for software not being part of Ubuntu or Mint or not having needed versions. (or build some smaller ones). I do not use flatpaks etc.
The only common software so far I could not find is Betterbird, modified and they say improved edition of Thunderbird. BB has the advantage of being able to continue using TB profile.
Instructions for compiling include download of 2GB repo. Not really practical. There is Arch installation, they say they can help, but not prepare repos.
There is Debian request, but I do not see that moving: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1072827

It would be useful in general to know which software is added to Mint repos. There is effort vs. need.
Not sure if this one could fit in there and if feasible to be included in the repos, but let us discuss.

[rcalixte]

Betterbird is available as a Flatpak. This should be available from the Software Manager. Considering that it is not packaged at either upstream of Debian or Ubuntu, the Flatpak is probably the better option until that changes.