Up&left don't work with Fire

I've tried the tutorial on my Linux box (Kubuntu 22.04) with Defold 1.4.4.
I can move the player in any of the 8 directions and fire a rocket anywhere expect to the up&left direction.
Curiosly, it doesn't get the combination of moving and firing in such direction.

This is confirmed by a "print(action_id)" that I put inside "on_input" function in the player.script file: when I press the up&left keys together with the fire (space) I only get a sequence of "[up]" and "[left]" while the other combinations give also the "[fire]" action_id.