Rose: I have FasterFox installed on my computer at home, and if no one else answers before then, I will take a look at those settings and see if anything jumps out at me. Probable some kind of "performace" thing FasterFox does is clearing that data out - to help make firefox "faster".

When I loaded it at home, I played with the setting but did not find any difference... which is why I haven't loaded it on the computer that I'm using now.

But if FasterFox is the only change - most likely that is the cause of the problem.