@ezio @nay are you running out of memory? I find that firefox (or rather icecat, which is just rebranded firefox esr) will just keep eating memory until my system becomes unusably slow and freezes because I don't have any swap and I have to manually invoke the oom killer with sysrq f (I should probably set up swap, there's an extra 32GB SSD in my laptop that I'm not using for anything, but I stopped using swap on my previous laptop because it would start swapping unnecessarily and that would make the system really slow)