Packaged game is locked in left top corner


I am working on a blueprint project. I packaged it for Windows 64 bits, and when I launch the executable, the window is in the top left corner, the title bar is hidden because outside the screen, and I can only see it if I resize my window.

Note that I work on an empty blueprint project and I removed pretty much any starter content there was because my app is UI only.

Here is what I tried that did not work :
-resize the window resolution with a command line execution
-set WinX and WinY with a command line execution
-execute command line fullscreen twice (to set fullscreen and unset it, to see if something would happen)
-set fullscreen mode with game user settings and applying resolution settings
-use a .ini file with options set to what I wanted

Please note that all of these things above worked ONLY when testing with a standalone game or launching the level on my pc, but did NOT HAVE ANY effect once the app was packaged.

Thanks in advance.

Maybe you have found these already but if not try here

this follows on from here:-