I have a home workstation box running Gentoo Linux. The desktop environment is KDE Plasma, currently at 5.11.5. And that's apparently not a good combination with the current NVIDIA driver. In the past I have seen occasional broken OpenGL compositor behavior, when a window suddenly flickered to black until redrawn, however otherwise everything worked properly, and I did not bother investigating what was a known but rare annoyance. Recently, however, I have found that the problem got much worse, screen occasionally turned to solid black, and X11 the driver produced an infamous "XID 31" log message.
The problem is not fatal, switching to a text console, restarting kwin_x11 and switching back to the desktop restores sanity while the rest of the session remains running, however it became frequent enough to become very annoying. I was also afraid that whatever was confused enough to access the wrong video memory address (what "XID 31" is according to NVIDIA), may also do something worse -- leak objects, corrupt GPU data or crash the driver.
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Update (2018-02-15): It looks like the problem was fixed in KDE Plasma 5.12.0 -- I have not seen it after upgrading to 5.12.0 (later 5.12.1) and reverting from Compton to KWin compositing. I am not entirely sure about it because the problem was intermittent to begin with, and it may be that the new version simply doesn't hit the conditions that trigger it as often as the old one did. However so far all windows are displayed properly, and no "XID 31" log messages.
Update (2018-02-18): 5.12.1 still managed to produce an error:
[721975.776488] NVRM: Xid (PCI:0000:07:00): 31, Ch 00000020, engmask 00000101, intr 10000000
So the combination of KWin compositor and NVIDIA is still broken. Switching back to Compton.