Mac, FF up through 4.0, "Refresh" doesn't fix slowness; undo it to recover extensions?
Best current guess is that flushing the "dyld" cache with Onyx seems to fix the problem for a few days or a week before it returns. The slowness (spinning rainbow) is by far the worst in Firefox tho' other apps and Finder also begin to show it once it starts.
Alle antwurden (3)
Unfortunately the extensions need to be reinstalled. Please first try these steps:
Correction, the default extensions will still be there.
Bewurke troch guigs op
In theory, you can recover the settings from the Old Firefox Data folder after a Refresh by copying its contents to the right spot. This is the only thread I remember about doing that on Mac, and the user didn't report back on whether it worked: https://support.mozilla.org/questions/1074549
Actually, here's a second one with no report back on whether it worked: https://support.mozilla.org/questions/1058258