Linux Keyboard controls don't work in Linux build



Linux users playing my game DASH can't press two buttons at the same time? It's a platformer (so you press several keys at the same time all the time) and there is no way I am redesigning the controls and mechanics because of this.

All my keyboard check code is simply standard gml. Nothing which would trigger any odd behaviour in my Windows build.

Can anyone tell me what the solution to this problem is? I checked out lots of stuff prior to deciding to port for Linux but I didn't read anywhere that Linux users can't press two or more keyboard buttons at the same time???

Any advice would be widely appreciated, not only be me but the many Linux users waiting for an update.

Thank you