Is this a problem with _RESIZE or expected behavior?

[mnrvovrfc]

Is your program influenced by $CONSOLE:ONLY?

This is a PITA away from Windows, and I don't know anymore about CMD.EXE which at least on Windows7 I remembered its other-worldly behavior with maximizing its window.

This is the reason why I first asked this: not everybody seems as determined as you to find holes in QB64.

Many things aren't supported on Linux such as _SCREENIMAGE because it would have to detect what GUI toolkit is being used, and other things about X-org or Wayland. This is only on the Linux side. Believe it or not, maximizing a program window is one of them. On Windows it would require calling something from the Win API and checking out the "classes", as it's required to put a window inside a window for applications that support documents opening in their own windows.

I ran a short test on Manjaro Linux, printing out the results of _WIDTH(0) and _HEIGHT(0). After running in ordinary SCREEN 0, I maximized the window. The screen didn't adjust according to PRINT statements. In other words, a number of lines at the top was left blank while the program I wrote resumed its business.

Granted, _FULLSCREEN doesn't work in this case neither because that requires hiding the window frames and title bar.

Maximizing an app window was something QBasic didn't have to worry about because it was always expected to be run under 16-bit MS-DOS. M$ BASIC PDS v7.1 followed along with this pretty much. That's why QB64 inherited it so far.