To get the old behavior of putting messages back in their initial
opened/closed state, use a prefix argument, e.g., C-u =.
+Attachment buttons can be used to view or save attachments.
+
+ When the cursor is on an attachment button the key 's' can be used
+ to save the attachment, the key 'v' to view the attachment in the
+ default mailcap application, and the key 'o' prompts the user for an
+ application to use to open the attachment. By default Enter or mouse
+ button 1 saves the attachment but this is customisable (option
+ Notmuch Show Part Button Default Action).
+
Library changes
---------------