I have a commercial app that was deployed in late 2018. It runs on Windows and requires Fullscreen=true to eliminate the taskbar at the bottom of the display. The app is generally used with multiple displays with the Main display (identified as Screen 1 in the Windows display settings) used for an application that is independent of my app. I received a tech support request from a customer who is using HiDPI laptops for the Main display with a Windows scale setting of 150%. His systems have two additional displays that are not HiDPI and have a scale setting of 100%. When the display used for my app is placed to the right of the Main display through Windows Display settings, the window for my app splits across the Main display and the display to the right. Since the window is in Fullscreen mode, it cannot be dragged to the desired display to correct the placement. I created a test app in C++ to determine if this was a Windows issue. The C++ app does not exhibit this behavior. I have isolated the problem to the use of different scale settings on the displays. If they are all set to the same scale setting, the error does not occur. However, this is not an option because the text on the Main (HiDPI) display is too small to read for most folks with the scale setting at 100%. There are other issues that prevent setting the scale to 150% for all 3 monitors.
Has anyone else had this problem, and if so, is there a resolution?