2 points
Not enough detail in the comic to tell whether it’s a striker or hammer-fired pistol.
Most striker (and some hammer) automatics cannot be decocked without pulling the trigger on an empty chamber.
And got those that can, you either have to pull the trigger while holding the hammer back and lowering it manually, or by flipping a separate switch or button.
If it could be done by moving the slide back and pulling the trigger, then holding the trigger down while firing the gun would result in full-auto.