Dear all, Please see attached for a new version of my changes for adding 'other-tab as an option for org-agenda-window-setup. I think I've addressed all your comments, Kyle, but any more are welcome. It would be good if somebody who is using an older version of Emacs, i.e. pre 27.1, could test the error handling: set org-agenda-window-setup to 'other-tab and see if it fails properly. I only have v28.x on my systems! On v28.x, it seems to be working fine. thank you, eric -- : Eric S Fraga via Emacs 28.0.50, Org release_9.3.7-720-gbe5916