It’s normal if you use the Nvidia proprietary driver. Every notification leaks one fd, so if you get a lot of notifications it’ll segfault once or twice per day.

This was apparently fixed in version 590 of the driver which was released only recently: https://forums.developer.nvidia.com/t/fd-leak-with-explicit-...

So that must be why I'm not affected. I have a gtx1080 which can't use that driver. Good to know.