Graphical artifacts in regions outside GTK windows

Yesterday I started noticing strange graphical artifacts such as the one shown here:

Screencast_from_2024-01-30_19-56-31

My host system has not been updated since Thursday last week, and the artifacts seem to occur in close proximity to GTK windows, so I suspect the issue is related to the new GTK renderers.

The bug is not reproducible. I saw it about three times yesterday. At first I thought it occurred only in windows that were not foreground, but in the example above it happens outside any window.

I think I remember dragging the window and the artifacts moving with the window; however, I don't remember for sure and I didn't take a video showing that. I might be making that up.