When using the spacebar to scroll through a thread, hitting 'space'
when the bottom of the last message is visible should take the cursor
to the end of the buffer rather than immediately archiving the thread
and moving to the next thread.
;; This is not the last message - move to the next visible one.
(notmuch-show-next-open-message))
+ ((not (= (point) (point-max)))
+ ;; This is the last message, but the cursor is not at the end of
+ ;; the buffer. Move it there.
+ (goto-char (point-max)))
+
(t
;; This is the last message - change the return value
(setq ret t)))