Does anyone have an idea of how to do it or even if it’s possible? Because as I am paranoid I would like to close my Mozilla account.
BONUS: How to prevent the installation of new extensions from opening welcome pages because it’s very annoying thank you.
It only works on desktop, but I use Syncthing to sync the whole profile (with the cache etc folders excluded).
You do need to make sure the profile path is identical on both machines as it’s hardcoded in the extensions json file, and otherwise your extensions won’t work properly.
So long as you close the browser on one machine before opening it on the other, it will sync your open tabs as well.