+(define-button-type 'notmuch-button-invisibility-toggle-type 'action 'notmuch-toggle-invisible-action 'follow-link t)
+(define-button-type 'notmuch-button-citation-toggle-type 'help-echo "mouse-1, RET: Show citation"
+ :supertype 'notmuch-button-invisibility-toggle-type)
+(define-button-type 'notmuch-button-signature-toggle-type 'help-echo "mouse-1, RET: Show signature"
+ :supertype 'notmuch-button-invisibility-toggle-type)
+(define-button-type 'notmuch-button-headers-toggle-type 'help-echo "mouse-1, RET: Show headers"
+ :supertype 'notmuch-button-invisibility-toggle-type)
+(define-button-type 'notmuch-button-body-toggle-type 'help-echo "mouse-1, RET: Show message"
+ :supertype 'notmuch-button-invisibility-toggle-type)
+