@w96k
2 GiB?! I often feel like a relic trying to juggle things with the 4 GiB on my laptop, since everyone seems to have 16 GiB these days! So it's good to know I'm not alone.
Unloading tabs when you're not gonna use them for a while could help (if you keep a lot of tabs open like I do). about:unloads (in Fx 94 and above)
Also, uBlock Origin, if you don't already have it. Ads slow down the pages *so* much the difference is amazing. I actually have Javascript disabled by default in the uBlock settings too, which helps even more with speeding firefox up, but that may be too extreme if you're not used to it.