Summary:
Ability to split screen into 4 segments as opposed to the existing 2 horizontal segments.

Use case / Motivation:
With larger 4k monitors attached externally or eventually finding their way into the devices themselves there's lots of screen real estate that can be more easily shared by support of 4 way split screen.

Having an easy way of snapping to corners for 4 different browser/app windows would make it far easier to use this additional screen real estate.

Existing workarounds:
Resize windows manually into 4 segments.