Yes, but in practice I've experienced Firefox (at least under linux) getting killed by the OS when RAM runs low. I recently lost some low-priority reading projects after I couldn't recover the tab sets (they were opened months ago, so hard to dig back through history)
I've found myself using Sidebery and the manual 'unload' tab option quite a bit.
Interesting, because out of all the three browser Firefox should be the best at memory management, unloading tabs along with Sessions recovery.
But I have only ever used it on Windows and Mac. So no idea about Linux. You can do About:memory to check out which tabs are using more memory as well as manual memory compact.
Firefox also allows unlimited History, unlike Chrome which I believe you cant even have history for more than 90 days.
There is a memory problem on Firefox I only found out about a few months ago when it started happening to me after an upgrade, "ghost windows" that use memory and never get deallocated. Restarting Firefox is the only way to clear them.
Not my experience at all with 16 GB RAM. Perhaps a configuration issue? zswap and mglru do their job well here and the only issue with reaching tens of thousands open tabs in Firefox is that it tends to become noticeably slower at that point.
Firefox with any number of open tabs is stable on memory usage because it has a target budget for it, most of the oom situations come either from external processes or a spike from FF's own.
Its supper useful if you really want to make sure not to loose your session, as its serializes everything into files, which you can then even backup somewhere if you want. :)
I've found myself using Sidebery and the manual 'unload' tab option quite a bit.