Can confirm that this happens on mobile (installed via F-Droid on GrapheneOS). It will seemingly change countries or profiles mid day or overnight without a restart.

It is super annoying and causes sites I use to send me through all the verifications again / generate new tokens…

I have not witnessed this on Linux via flatpak but will keep an eye out…

All Geckos can sync if Mozilla Sync is enabled with an account. So you can sync say LibreWokf or WarwrFox on desktop to any mobile version, such as IronFoz. They do not have to “match”.