Prevent panes from overflowing the window (#3609)

This PR fixes an issues where it was possible for panes to overflow the
window (for instance, by having a large number of tabs in the tab bar).

Release Notes:

- N/A
a334a21f3eMarshall Bowers committed on 12/12/2023, 4:01:49 PM· committed by GitHubparentc0846d6
1 file changedLine totals unavailable