The window gets repainted with the updated contents (new size), but then somehow ends up being repainted again with empty contents (white).
Debug paint log:
client draw may_paint_now() paint pending= 0 , paint queue length= 1 client draw do_paint( 2388 bytes of webp data 775 x 927 at 0 , 0 ) focused= true client draw request_redraw for Window(1) client draw swap_buffers client draw decode time for webp sequence 21 : 5 , flush= 0 client draw may_paint_now() paint pending= 0 , paint queue length= 0 client draw animation frame: 1 windows to paint
Workaround in r22901: we just force a refresh shortly after the end of the resizing.
I have no idea why sometimes things get wedged, and no time to investigate further.
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/2321