+ "multipart/related")
+ "Which mime types to hide by default for multipart messages.
+
+Can either be a list of mime types (as strings) or a function
+mapping a plist representing the current message to such a list.
+See Info node `(notmuch-emacs) notmuch-show' for a sample function."
+ :group 'notmuch-show
+ :type '(radio (repeat :tag "MIME Types" string)
+ (function :tag "Function")))