I'm on Kubuntu 22.10, but I'm fairly sure I've seen this issue since at least 18.04. In general, I set up 4 virtual desktops in a 2x2 pattern, and I pin my Chrome window with a bunch of tabs open to my left monitor so that it's up in all 4 virtual desktops. Now and then, most frequently in Chrome, the entire browser window starts to stutter between its last couple of rendered frames, either when I'm scrolling or watching a video being the most noticeable, and then it just freezes entirely. But the application didn't freeze. It's actually still working under the surface, and if a video is playing, I can still hear it. I mentioned I pin my browser window to all virtual desktops, and if I scroll between those desktops, I can see it rendering normally again for a second or two during the desktop scrolling animation. If I pull a tab out of Chrome into a new window, the new window behaves fine. If I merge the tab back into the previous window, it doesn't fix the problem, but if I pull every tab into the new window, they're all fine. Basically the only thing I've found that fixes this is to kill the program that's misbehaving and relaunch it.
Chrome is not the only program that does this; it's just that since I have it open all the time, it's the place I'm most likely to run into it. I'm very unable to recreate this problem on demand, but it happens probably a few times per week. The one place I saw it most consistently was when I was recently playing Dishonored: Death of the Outsider via Steam. Alt+Tabbing out of the game window or scrolling through virtual desktops appeared to often cause this problem for the game itself, enough so that I never wanted to lose focus of the game window for fear of making this happen again and having to close and re-open the game, going through arduously long opening credits videos. I've also seen this problem twice in the past week with my KDE notes widget on my desktop background that I use for to-do items.
Does anyone know what's causing this problem or how to fix it? Failing that, does anyone know what logs I should be pulling, if any, to attempt to diagnose it?