>if I run my app which starts with windowstate maximized on a win 10 pc with its font size bigger than 100% (in my example 125% or 150%), it covers only a part of the screen like in normal mode. I have to dblclick 2 times to get it in "real" maximized mode. With Win7 there are nor problems occuring. What can I do or am I missing?
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Thomas, have you try to set the DPI-aware setting for your application?