PTB-WARNING: Flip for window 10 didn't use pageflipping for flip. Visual presentation timing and timestamps are likely unreliable!

[mariokleiner]

Probably running on Ubuntu 24.04 with standard Ubuntu desktop GUI, ergo probably this:

No pageflipping on Ubuntu 24.04-LTS with Ubuntu/Gnome desktop GUI

Try to click on the notification area in the top-right corner of your Ubuntu desktop GUI, where the various controls, battery / network etc. indicators are. I think GNOME desktop, and thereby its derivative the standard Ubuntu desktop, has a bug on Ubuntu 24.04-LTS that prevents page-flipping, unless you click there, which somehow magically fixes the problem until the next logout + login. Or install a different desktop GUI like KDE and see how that goes. I wouldn’t know, but assuming a GNOME b…

-mario