Saving Editor Layout in Xcode

Is there some way of getting Xcode to remember the layout of the editors you last used?

My 'go to' tab configures 3 Editor columns across my 34" screen. Every time I quit Xcode, it loses the column geometry when I next restart. It will open up the tab with the column widths completely mangled.

If I click to 'focus' on any of the editors, and then click again to 'un-focus' the same editor, it will restore all 3 to the way I left them when I last quit Xcode.

It's such a hassle! I'm sure I'm missing something really basic… any clues?

Thanks, Rob (PS this is Xcode 13/Monterey - but it was the same with Xcode 12/Catalina)