Could you add support for a "grab" action? A press-and-hold gesture could initiate the grab, keep it active while held, and release it when the gesture ends.
This would work well with the MX Master 3's capacitive side button, allowing me to grab and manipulate objects while the button is pressed.
there is no such thing as a grab on macOS. There might be something like it in some specific applications. Where are you trying to use this?
Hey 
Go to photos and zoom in, then click and move the image. You'll see the grab hand I'm talking about. It's the same action as if you did a two finger scroll movement with your trackpad.
I think you're right that it's not global.
What I'm trying to do is replicate the two finger scroll with the capacitive side button on the MX3
