Impossible to key-press three near keys I have never noticed this before, but it seems like MacOS prevents certain key combinations to be pressed.
For instance, try pressing at the same time the keys z s and c on a standard Qwerty keyboard. This works and should write something like &quot;csz&quot;. But if the three keys are all adjacent, for instance z s and x, MacOS drops one or two, or all of them, for instance giving you just &quot;z&quot; or &quot;zx&quot; or nothing at all. I've noticed this consistently across multiple Mac devices.
Since I'm programming a software that heavily relies on various key combinations (it's a virtual MIDI keyboard that transforms the computer keyboard into a MIDI controller), how to disable this behaviour?
This is a hardware limitation of the built-in keyboard (and most non-gamer consumer keyboards)
You have to get a separate keyboard which supports NKRO (N-Key Rollover).
There might be issues with macOS compatibility with some n-key rollover keyboards USB keyboard acting strange with MacBook Pro
So check if it's compatible before you buy