[autoexec]

If I really wanted to keep a record of all the sites I've been to for historic reasons like this person there are far easier/better ways to do that. I'd even set it up to download a local copy of the sites I visit so that they'd be there even if the sites went offline.

I have 298 tabs across 8 windows open right now and I can already tell firefox is about to crash at any moment. I go to about:memory and mash the buttons in the "free memory" box to buy some extra time, but eventually firefox goes down in flames and I lose all my open tabs. When it does finally crash Firefox can never restore my tabs, but I blame myself/my settings for that.

When things get to this point where I know firefox will die soon I end up bookmarking them all or even copying each URL into a text document with dreams that I'll go back to them after my browser has been closed and re-opened, but I almost never manage it. At least I have the option I guess and I know that if I ever do I'll find things that are of interest to me. There's just no shortage of other things that are of interest to me online so the newest stuff tends to win out.

[_Microft]

As long as you don't have private browsing windows open (these won't be restored), you should be able to close Firefox and have it restore all tabs after a restart. It will unload all tabs, i.e. they won't use memory until you focus them again.

[timbit42]

Have you tried Auto Tab Discard to reduce memory usage?

I have Firefox set to reopen tabs when it starts and, on the very rare occasion it does crash or the power goes out, the tabs are back when I reopen Firefox.