On a laptop (windows 10), using an external monitor, if you disconnect the external monitor then the font/style/palette of the application gets corrupted.

This also occurs if the laptop goes in power saving mode (dual switchable graphics cards).

This problem affects also QtCreator, not only my own application.

To reproduce it:
Connect the laptop to an external monitor and swith display to it
Launch QtCreator
Disconnect the external monitor, QtCreator is now shown on the laptop's screen
Hover the mouse on the QtCreator menubar or other part to see the font and style changing.

The problem is more serious in our application, I suppose because we use specific font sizes.

I have filtered out WM_DISPLAYCHANGE event using a QAbstractNativeEventFilter and the problem disappeared, but I am afraid that I probably broke something doing so.

Thanks
Philippe Lelong