Our defcustom call was missing the 'notmuch group, which emacs was
nice enough to warn about during compilation.
(defcustom notmuch-search-authors-width 20
"Number of columns to use to display authors in a notmuch-search buffer."
(defcustom notmuch-search-authors-width 20
"Number of columns to use to display authors in a notmuch-search buffer."
+ :type 'integer
+ :group 'notmuch)
(defcustom notmuch-search-result-format
`(("date" . "%s ")
(defcustom notmuch-search-result-format
`(("date" . "%s ")