resizeable game window doesn't scale right on Linux either (but the bug is a little different from the Windows bug)... [u524]Reporter: time-killer-games | Status: open | Last Modified: September 30, 2017, 07:24:17 PM
Those bugs only happen for "Keep Aspect Ratio" and "Full Scale". Now, as for "Fixed Scale (in %)", if the percent is less than 100%, the game window stays at 100%, and only the actual game contents is scaled down to under 100, leaving a black letter box on all four sides. The game window itself should scale down to that lower percent like the game contents are. Also, if you set the "Scaling" to "Fixed Scale (in %)", the GM behavior is that the game window can't be resized under the specified percent. i.e. if you have the fixed scale set to 100 and try to resize the game by dragging the window border with the mouse anywhere below 100%, it won't let you go below that size. hence, being called a "fixed size". You can resize the window above that size and the game produce a letterbox, in this case that's how GM does it, but the only thing you can't do is go BELOW the specified size in percent.
Like the Windows bug report, scaling works how it should when fullscreen, and these things are only an issue in windowed mode with a resizeable window.