it's probably the "you only notice when it doesn't work" situation, but my experience with firefox on ram limit has been a lot about tabs forgetting the url in them

as in, I click "open in new tab", some time later I switch to them... only to get hit with "new tab", even though a moment ago it displayed tab name and I could right click -> bookmark to preemptively copy the address

Try the "Auto tab discard" extension. It allows me to have hundreds of tabs "open" and (in combination with Tree Style Tabs) largely blur the line between "browser sessions" and "bookmarks".

Far better than bookmarks.

Bookmarks do not store click history, the trajectory you took to arrive at the page. With tabs, the contexts is a backbutton away.

Yeah, agreed. The built-in tab discarder only kicks in when there's actual memory pressure, so can sometimes be a bit precarious. Auto tab discard happens way before that, so tends not to be affected in the same way. I guess it uses more i/o in total, but it's not noticeable on a system with a fast-ish SSD.

It can still be a bit iffy when memory's really tight, but even then a simple tab reload is usually enough to fix things.

Haven't had that happen, but what I have had happen is that I open in a new tab, and it just displays this spinner in the middle of the window while on the tab. It never loads. I take the URL from the address bar and drag it into yet a newer tab and there it loads. Then I close the original new tab. Sometimes I gotta do that a few times for the thing to load. I tend to open in new tab with middle click, if it makes a difference.