[1.21] Duplicating a pane after changing the settings uses the _old_ settings?

[zadjii-msft]

At top: the first pane I opened, when I booted this portable instance of the Terminal.

I changed a bunch of settings - scheme, scrollbar marks, font weight. That first pane got the updated settings perfectly.

Then I split a pane - that new pane got the original settings out of the pane.

I'm guessing that this was broken around #997. I'm gonna call this not blocking, but something we should service.