Firefox is totally doable on that much RAM. Not going to be pleasant, but usable. You want to strip down as much resource usage as you can: inside Firefox throw in uBlock Origin and Tab Unloader; outside Firefox use a stripped down desktop like XFCE or just a straight low resource window manager with no desktop environment (I was a big fan of WindowMaker back in the day).

I hate the default way most browsers handle tabs. Moved over to this setup years ago and I’m definitely never going back.

Firefox plus either Sideberry or Tree Style Tabs - both will organize your tabs vertically along the side of the window in a tree format. Follow a link in a new tab, it opens up as a new branch under the current one.

Pair that with Auto Tab Discard to keep memory usage down, and something like Open Link with New Tab to automatically open links across domains in a new child tab.

Now I tend to just collapse trees of related tabs and further organize broad related subjects in windows.