When the part has no filename it is reasonable to guess it is not a part for saving or other normal attachment things so default to toggling viewability. Possibly this should be customisable but the 4 main actions (save, view, open with, toggle viewability) all force that particular action so it is easy for the user to get round if we do make a mistake. --- emacs/notmuch-show.el | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el index 9a33d28..c8c1657 100644 --- a/emacs/notmuch-show.el +++ b/emacs/notmuch-show.el @@ -1988,7 +1988,12 @@ the user (see `notmuch-show-stash-mlarchive-link-alist')." (defun notmuch-show-part-button-default (&optional button) (interactive) - (notmuch-show-part-button-internal button notmuch-show-part-button-default-action)) + (let* ((button (or button (button-at (point)))) + (filename (and button (button-get button :notmuch-filename))) + (handler (if filename + notmuch-show-part-button-default-action + #'notmuch-show-internally-show-part))) + (notmuch-show-part-button-internal button handler))) (defun notmuch-show-part-button-save (&optional button) (interactive) -- 1.7.9.1