(define-key map ">" 'notmuch-search-goto-last-thread)
(define-key map "=" 'notmuch-search-refresh-view)
(define-key map "\M->" 'notmuch-search-goto-last-thread)
(define-key map ">" 'notmuch-search-goto-last-thread)
(define-key map "=" 'notmuch-search-refresh-view)
(define-key map "\M->" 'notmuch-search-goto-last-thread)