[Interest] application appearance changing when laptop goes in saving energy mode

[maitai]

Hello

On Windows, some users are reporting that the application style (font? 
palette?) is changing when laptop goes in energy saving mode, and 
becomes more or less unreadable (white font on white background, etc). I 
have seen that myself also a couple of times but I'm unable to reproduce 
it.

When it occurs, putting the laptop back on power does not fix anything, 
and the only way to get back the proper appearance is to restart the 
application. If you start the application when in battery saving mode, 
no problem. The application is widget-based (QMainWindow, 
QGraphicalScene, QMenubar, etc), Qt is 5.5.1 but that was reported also 
with previous Qt versions.

As I said this occurs only for a few users, and I cannot reproduce it. 
Maybe it's connected with the laptop changing GPU, I don't know.

Does anyone knows what could possibly trigger this, and if I can catch 
it somehow either to avoid it or reload style/palette/font/etc when it 
occurs?

Thanks
Philippe Lelong