This is for 23.12beta2 but also for some previous versions (23.10, for instance).
Using the GeForce Experience app, a new video driver can be updated roughly every month or two, with the latest optimizations for various games and so forth. This is downloaded directly from NVIDIA, rather than going through the usual Windows Update process.
During the install process, as the new driver is installed, the entire screen goes blank for a few seconds and then refreshes. After the screen refreshes, all the other app windows such as the Chrome browser appear normally, but all of the Anki windows are now completely blank white, except for the title bar.
Minimizing the various Anki windows and then restoring them doesn’t fix it, nor does anything else. The only solution is to terminate Anki and restart it.
Minimizing the Browse window and restoring it by clicking on its taskbar-adjacent thumbnail leaves the Browse window blank white.
Minimizing the Browse window and restoring it by hitting the “b” shortcut key from the (equally blank) main window turns the Browse window blank black. A couple of minutes after this, Anki appeared to crash.
TL;DR:
In itself this is obviously a minor issue, but perhaps it suggests that some refresh event within Qt is not being caught or handled correctly? So perhaps unraveling this might solve some other blanking problems that get reported occasionally.