Auto hidden toolbar glitch

Not quite a bug, the toolbar is auto hidden vertical on the right, there is a full-width spacer after the top settings icon and a full-width spacer before the bottom trash bin, this centers the middle icons nicely, like so

But when the toolbar is un-hidden the icons all appear at the top then they are moved to their proper positions, looks glitchy and puts off the 'mouse-targeting' from memory of where the icons should be.

Thanks, a fix is on the way. (If not in 12.21, then in 12.21.1.)