Keith,

I have four monitors, one of which is above the others. When I use the span function, I get a skinny window on my primary.

What I would expect is that the span function would find the maximum width it could create going from the current monitor right and left, then find the maximum height span on the found maximum width axis. I would expect it to ignore monitors not aligned with the current monitor.

Attached is my actual result, the window highlighted in purple.
I've also attached what I expected and my monitor selector to clarify my layout.

Here's my monitor selector.