Thanks @firefox for totally F'ing me. Suggested I restore browser for faster performance. Wipes out all bookmarks & history. Backup error.pic.twitter.com/tqtVsVl7TR
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If I understand correctly, the original reporter was prompted by Firefox to do a profile refresh and it failed to create a viable profile.
I'm 95% sure that a Refresh doesn't actually overwrite the old profile, so the data should still be there, but not used by default.
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