+:index:`notmuch-multipart/alternative-discouraged`
+
+ 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.
+ The following example function would discourage `text/html` and
+ `multipart/related` generally, but discourage `text/plain` should
+ the message be sent from `whatever@example.com`.
+
+ .. code:: lisp
+
+ (defun my--determine-discouraged (msg)
+ (let* ((headers (plist-get msg :headers))
+ (from (or (plist-get headers :From) "")))
+ (cond
+ ((string-match "whatever@example.com" from)
+ (list "text/plain"))
+ (t
+ (list "text/html" "multipart/related")))))
+