[sciurus]

IIRC this only occurs if you are using your distro's firefox package. If your package manager upgrades firefox out from under it, things break and you have to restart Firefox to get back in a sane state.

If you use Mozilla's build of Firefox and it's built-in update system I think this won't happen.

(Disclosure: I work for Mozilla but not on this)

[addicted]

I believe this also happens with certain pre release editions (Nightly, which I use) which is absolutely reasonable.

[prionassembly]

Would you agree it’s still bad UX if it only happens to people who haven’t gone out of their way to get a “good” Firefox?

[ben0x539]

It's bad UX but how far should Firefox go out of its way to support the situation where a (from its perspective) third-party package manager just deleted all its files, replacing them with subtly different/newer ones?

[dastx]

Unlike Microsoft and Apple, on Linux you're never forced to upgrade. Thus, when you do upgrade, you should really be checking what packages are upgraded. The alternative to such a page would be to require you to stop Firefox before the updates start. So it is still a trade off.