the resolution menu suggests 640*360 px as a resolution, but when I select it
and try to play, the game crashes

FreedroidRPG 0.16rc2-3-g72d74df encountered a problem in function:
widget_background_load_3x3_tiles
The following tile set cannot be loaded: widgets/quest.
(minimum required widget size: 327 x 387 - available widget size: 253 x 300)

You need to run the game in a higher resolution mode


Can we somehow hide resolutions that we know will be broken anyway?

Lowest resolution in the listing is 640x480.
So, was this issue already fixed ?

Ah sorry. You mentioned the 'menu', not the output from '-r 99' cmdline.