I’ve encountered some sort of bug with an unknown trigger. A firefox window will suddenly hang (often while I’m in the middle of scrolling) and stop responding. I can still interact with other windows completely fine, even other firefox windows. If I drag around the window that stopped responding, it leaves a trail behind (similar to what I remember seeing back on windows xp during a crash, although this trail won’t stay indefinitely, the “ghost” windows will disappear as new ones are created).
I’ve also noticed that while the hung window doesn’t appear to respond to any input, I can drag the tabs away from the window, and a new firefox window will open.
I have no idea what’s causing this, but I’m honestly more fascinated by it than annoyed. There’s nothing in the journald log, nothing in the x.org log, and nothing in the kernel log.