Hello, This issue seems somewhat unique. Using Firefox on 85.0.1 64-bit (but existed for a while) on Ubuntu 20. My laptop is a dell Inspiron with an nvidia GeForce MX250 and driver version 450.102.04 (but, again, this problem existed on earlier drivers). I dual boot Windows 10 on this laptop and use firefox there, but do not have any issues there. Sometimes Firefox will just start unloading pieces of the web page. It's not that the tab is crashing, the parts just start visibly disappearing, and I can see other applications or my wallpaper behind it. When a youtube video is playing, the sound will keep going (without issue) even after the video stops and eventually disappears. I can reproduce this problem by having a youtube video playing in a tab, closing my laptop to idle it, and reopening it and logging back in. Doing so ensures this issue happens immediately, but the issue will still occur at other times, with or without a youtube video playing (that's just what I use to test the issue as per my example given). Going through existing articles, I followed the steps in this one: https://support.mozilla.org/en-US/questions/1275189 since my issue seemed similar to theirs. Restarting Firefox in safe mode did indeed stop the issue! Then, I followed the steps to diagnose if it was an extension or hardware acceleration. (I use the default theme so that's not the issue.) Disabling hardware acceleration didn't solve the problem. Okay, maybe it's not that, I'll turn off the (only) extension I have... And that didn't work either. I turned off hardware acceleration and my extensions, and the issue is still being produced. So, I'm trying to understand, if safe mode only deactivates extensions, themes and hardware acceleration, why does the issue go away in safe mode but persist in normal mode with all extensions and hardware acceleration turned off on the default theme? Attached are images of the "unloading" issue. Any help would be appreciated.