** Rmail issues:
-mail/rmail-spam-filter.el: check it still (?) works
+mail/rmail-spam-filter.el: It seems (?) to work.
+At a few places, it leaves the raw mbox buffer visible, either while
+it displays a prompt or waits. This is poor, but it does not seem
+straightforward to show a message at that poiny without messing up
+rest of get-new-mail. (See rmail-get-new-mail-filter-spam, end of
+rmail-get-new-mail-1, and end of rmail-spam-filter for FIXMEs.)
Update the rmail (and gnus) manuals for mbox rmail.