Why can't the devs have it update in the background or on next startup? I was in the middle of my work when I got this. Now I need to close everything and go through all the logins and 2FA again. 😡
Chrome is much better at this, hands down. It has never interrupted me the way Firefox does during updates.
This happens when FF updates out of band. Ie package manager.
Your windows updates are probably set to also get applications when it updates. Turn that off and see what happens (next month).