Increase thirds snap areas from 3 to 9 and allow hot key assignment.

I use the thirds feature with hot keys a lot , however I'd like to see it extend to 3x3 on monitors to be truly useful, the custom snap areas don't function in the correct way to make this happen and it's very distracting to see snapbox outlines flash up (nevermind nothing aligns properly)
So to be clear
Extend left middle and right thirds to variants
left - top middle bottom third
middle - top middle bottom third
right - top middle bottom third

you can use the "custom move/resize" action to do this. (FYI you can make snap areas invisible if needed, but the action might better suit your use case)