Re: New package `outline-occur'

 > It doesn't look like the manual was updated in
 > https://cgit.git.savannah.gnu.org/cgit/emacs.git/commit/?id=8a88f3ed5aeece4a7c8edbebc83ed52479fbbfab

I added a few more references to both Elisp manual and 'display-buffer'
doc-string now.  Please have a look.

 > It might be worth mentioning special-action and extra-action in this list too?

We do not document them because 'special-action' processes
'special-display-function' which is obsolete since Emacs 24.3.
'extra-action' OTOH processes an old form of the ACTION argument of
'display-buffer' and the optional FRAME argument which should not be
used in Lisp programs any more.

Thanks, martin