https://bugs.winehq.org/show_bug.cgi?id=55583
--- Comment #1 from Stefan Dösinger stefan@codeweavers.com --- This affects the linux_newtb-debian11 machines right? It is using fvwm2 according to the description. Are you using UsePPosition for them? (See wine commit c7d748d2e5).
Even with fvwm's default of randomly ignoring client position requests the test seemingly passed previously, so I'll try to do something about it. I can't promise that I can do more than add a flaky, or revert the patch and add a flaky to the original WM_ACTIVATEAPP failure.
I think you confused two different windowposchanging failures - the one where a WM_WINDOWPOSCHANGING message arrives but is not expected, and this one here, where we want a WM_WINDOWPOSCHANGING notification.