what do you mean by : the bug appeared in version 5.9 ?
did it exist in version 5.8 ? (ok, it didn't according to your 1st post in 5.7)
because recalbox is more or less the equivalent of the official batocera 5.0
i don't think it's related to the hotkey patch, but possibly i upgraded it too.
can you confirm if it works with 5.7 or not, i'll check the modification. however, i think it's a bug in the emulator itself, i can fix it, but i need to reproduce it myself to not loose too much time.