I work under GNU/Linux and have two identical displays. When I launch a JUCE application, it is launched on the first display, and I cannot move it to the second one (when I move it to the right in the “direction” of the second screen, once it reaches the border, it goes to the left border of the first display rather than to the second one).
It is perhaps related to an assertion failure in juce_Displays.cpp on line 366 (at least under GNU/Linux). Each display is represented by a node, and this line tests that the “parent” member is set correctly. In my case, for the first one (node/display), the parent member is correctly set, but for the second one the parent member is nullptr.
This sort of breakage is normally highly dependent on the particular operating system, window system, window manager and so on.
Please could you let us know what operating system version, window system, and window manager you are using, along with any other details that you feel might be relevant.
I am using the latest version of Ubuntu (Kernel 5.13.0-37) with KDE (Plasma 5.22.5 et Frameworks 5.86.0).
If you need more information (or if you want that I debug some precise part), I am available.
Can you find out whether you’re using X11 or Wayland?
I am using X11.