Ubuntu 23.04: can't send (some) windows to back

[Paul Smith]

On Mon, 2023-07-24 at 16:13 -0400, Little Girl wrote:
> > Maybe I'll try filing a bug on Launchpad against one of these apps
> > and see if anyone can tell me what's going on.
> 
> Hopefully they can help.

Appears to be https://bugs.launchpad.net/mutter/+bug/2015577

It was filed back in April but no action on it so far.  I guess most
people don't use this feature?  I can't live without it really.