defaults com.apple.dock pinning start
killall Dock

and

defaults com.apple.dock pinning end
killall Dock

which anchor your dock left or right, top or bottom, depending if it's positioned horizontal or vertical. Makes much more sense to me... why have it grow annoyingingly in both directions every time you start/stop/activate apps, when you can have it grow in just one?

Muscle memory is all.

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