(define-key map "t" 'notmuch-search-filter-by-tag)
(define-key map "x" 'kill-this-buffer)
(define-key map (kbd "RET") 'notmuch-search-show-thread)
+ (define-key map [mouse-1] 'notmuch-search-show-thread)
(define-key map "+" 'notmuch-search-add-tag)
(define-key map "-" 'notmuch-search-remove-tag)
(define-key map "<" 'beginning-of-buffer)