Fix Version/s: None
We have a similar-looking missing repaint where horizontal scrollbars usually could be, but are not when we have the issue. see video.webm
Yes, one might think it's shell32..., but since it also affects rapps application, I guess it might be WIN32SS too like the thing you just adressed...
Can be observed in r71688, but also since a long time in the past...
I hope this is no duplicate of some existing ticket.
Are you warmed up for another great achievement?