Window disappears when monitor is disconnected

The window of application disappears after monitor output is turned off/on.

The app is running on the 2nd monitor, on the separate X11 screen.

To reproduce the issue:

xrandr -d :0.0  --output DP-0 --off; sleep 1; xrandr -d :0.0 --auto

(assuming window is running on X11 DISPLAY :0.0 and physical output is DP-0)

The process remains, X11 window disappears ('wmctl -l' doesn't show this window).

The original application was Telegram-desktop (statically linked with Qt-6.4.2),

but I was able to reproduce the issue using

qt-everywhere-src-6.4.2/qtbase/examples/widgets/painting/basicdrawing;

Applications linked with Qt5 are not affected.

For example, running Okular linked against dev-qt/qtcore-5.15.8-r1 does NOT demonstrate the issue.

Xorg.log during switching:

372776.380] (II) NVIDIA(0): Setting mode "NULL"
[372777.479] (II) NVIDIA(0): Setting mode "DP-0: nvidia-auto-select @1920x1200 +0+0 {AllowGSYNC=Off, ViewPortIn=1920x1200, ViewPortOut=1920x1200+0+0}"

Note: the issue is 100% reproducible, feel free to ask for more information, if needed.