Self.Window.Width = NewWidth
Self.Window.Height = NewHeight
This works. Except on Mac it animates each dimension, which probably means setContentSize: is being called twice. It looks ugly. I haven’t been able to figure out a declare that will work. I’ve tried getting the handle with Self.Window.Handle and calling setContentSize: on it, but the popover does not resize and it’s empty instead. So I’m betting Self.Window is not the NSPopover. Anybody have any better ideas?