mutt(1) on Linux
The text 4b743d76f146, as Debian 2.2 (Potato) shipped it.
The Mutt Mail User Agent
Flags it lists
-
-F -
-H -
-R -
-Z -
-a -
-b -
-c -
-e -
-f -
-h -
-i -
-m -
-n -
-p -
-s -
-v -
-x -
-y -
-z