My Firefox has been stumbling lately with Flash. I had an older version, not sure which. Pages that would not run in FF would in Chrome. I was cued to update flash. After installing new Flash (from official Adobe website), it closed my current FF browser. When I reopened it, all my bookmarks, history, toollbars were gone. Why did this happen and how do I get them back? Please tell me I can get them back! Thanks.
Flash Player (or the installer) has nothing in it to alter ANY personal settings in Firefox.
The installer places a plug-in in a pair of folders where Firefox is able to locate it (C/Windows/System32/Macromed/Flash and C/Windows/SysWOW64/Macromed/Flash).
That's all. You do need to close the browser before the plug-in can be installed, but that's because the folder can't be modified while it's in use. That doesn't have anything to do with bookmarks, history or toolbars as they're in a separate folder altogether (Users/[user]/AppData/Roaming/Mozilla/Firefox/Profiles/[8-digit#]default).