Zone list "+ x more" logic is too sensitive

[SteveMicroNova]

See images. The "+1 more" replaces the equally long Zone 6 just by shrinking the width of the window a few pixels, and does so while the containing box still has room for 4x2 zones. Change this logic to be more sensible.

[SteveMicroNova]

I would use a combination of this and potentially some amount of math using the width of each zone in the grid to decide when to collapse them