[throwaway182943]

That worked, thank you!

As a side note, the value for that setting got reset after I restarted firefox.

Also, I uninstalled the fix by simply removing the extension in about:addons. Is this the correct way to do it?

[gpm]

Yep, you're all good. I'm surprised it let you remove the fix from about:addons but I wouldn't worry about it.

That value resetting is expected, it's the time when Firefox thinks it last checked signatures, it resetting just means this convinced it to recheck as intended.