I’d been dealing with an odd issue for a while in that Firefox would not remember my tabs from the prior session when I exited the browser gracefully (Firefox Menu > Quit). Now if I did a restart (such as when installing an add-on or even with the restart button that chromEdit Plus adds) or if the browser crashed (intentionally or unintentionally), when I restarted my session would be exactly as it was. I had in the general settings When Firefox Starts to Show my windows and tabs from last time. I had devised an odd work around to preserve my tabs in a situation where I would have to actually quit the browser (restarting the computer after installing Windows updates), that was to intentionally crash the browser via Nightly Tester Tools Crash Me! option.
I posted about this last night over on mozillaZine’s Firefox Builds forum as I thought it was something related to Firefox 8 Beta. Of course I was thinking it was more profile related, but I didn’t know why. I had tried a couple suggestions with no avail. Earlier tonight, someone suggested going to History > Restore Previous Session. So, I gracefully exited the browser and started up again to a blank tab. I then went to History > Restore Previous Session to discover it was greyed out. This got me to thinking may be I should take a look at my history settings (Tools > Options > Privacy Tab). The first thing I noticed was Firefox will Use custom settings for history. Upon reviewing the ‘custom settings’, I discovered while I did have Remember my browsing history checked, I also had Clear history when Firefox closes checked.
Well that explains why Firefox was having amnesia on a graceful exit. I unchecked that option (not sure why it was checked in the first place). After closing Firefox (gracefully), I restarted Firefox and all my tabs from my prior session were there. I went back into Tools > Options > Privacy Tab and now noticed Firefox will: Remember my history. It seems a bit contradictory to have options to both remember and clear history. So if you are experiencing this issue, check your history settings and be sure you are not having Firefox clear the history when exiting.