This is a general Qubes question. The same would happen with a Qubes Debian template. Qubes-Whonix won’t add any additional issues in this case.
Therefore this is the wrong forum. See also:
What to post in this Qubes-Whonix forum and what not.
No, they’re not. Templates home folder is persistent. But not inherited by App Qube based on that Template.
The complication is coming from the combination of two non-standard behaviors by two different projects:
- A) how Qubes implements (non-)persistence, and
- B) that Mullvad Browser (MB) is a binary installed in the home folder
Therefore it’s probably easiest to install MB in the home folder of an App Qube (or Standalone but that’s fully optional).
Installation of MB in Template will be difficult for most users until MB gets available as a .deb package, flatpak or similar. I wouldn’t hold my breath since this hasn’t happened for TB (Tor Browser) for approximately a decade already.
tb-updater (by Kicksecure / Whonix developers) might get support for downloading Mullvad Browser, tracked here:
This would simply this process.
Additional information:
For this you need a strong understanding of Qubes persistence. Maybe this helps:
Qubes-Whonix ™ Overview chapter Qubes Persistence in Whonix wiki
related: