mpv-player/mpv — pull request #1256 by rossy (2014-11-08 11:07:28+00:00)
Title: Open the window menu on Alt+Space

Fix for #1254. This is expected behaviour on Windows, but it seems like getting mpv to translate its own keyboard input (in 0ab3482) breaks it, so it has to be done manually. I found a similar workaround in the mintty terminal emulator, which also translates its own keyboard input.