In the past year, having Firefox for Windows set to ask you when to update seems a bit less reliable. I think the problems occur when I start up Firefox in a different profile. Although all profiles should follow my instructions on upgrades, it doesn't seem completely reliable.

Unfortunately, once that message appears, I'm not aware of any way to continue. I think because the upgrade was already installed and there is a mismatch between the firefox.exe processes in memory from before the upgrade and the files on disk now. It might be possible to continue work for a while in existing tabs on current sites, but nothing new.

Finally, please note that the about:config preference is a historical note from when Firefox changed from storing this setting in prefs.js and a hidden file named update-config.json under C:\ProgramData\Mozilla...

I not only have this same problem, but it happens every week now, because for some reason Mozilla has decided to release tiny updates every week, instead of packaging them together in larger updates so you only need to update once per two months or so.

It's infuriating to be kicked out of your browser all the time and lose all kinds of work and I'm baffled how anyone could ever think this was a good idea, or suggest it in a meeting and not get fired on the spot. What is going on at Mozilla?