From e1961c543a9871ee79ff36e7a11453397aede0d4 Mon Sep 17 00:00:00 2001
From: Nicolas Goaziou <mail@nicolasgoaziou.fr>
Date: Mon, 6 Apr 2020 14:30:35 +0200
Subject: [PATCH] ox-koma-letter: Handle empty hyperref LaTeX template

* contrib/lisp/ox-koma-letter.el (org-koma-letter-template): Value
for :latex-hyperref-template can be nil.  Handle this case.

Reported-by: Charles Millar <millarc@verizon.net>
<http://lists.gnu.org/r/emacs-orgmode/2020-04/msg00025.html>
---
 contrib/lisp/ox-koma-letter.el | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/contrib/lisp/ox-koma-letter.el b/contrib/lisp/ox-koma-letter.el
index 548204681..66394689d 100644
--- a/contrib/lisp/ox-koma-letter.el
+++ b/contrib/lisp/ox-koma-letter.el
@@ -748,7 +748,8 @@ holding export options."
                 (if (symbolp with-subject) with-subject
                   (mapconcat #'symbol-name with-subject ","))))
       ;; Hyperref.
-      (format-spec hyperref-template spec)
+      (and (stringp hyperref-template)
+	   (format-spec hyperref-template spec))
       ;; Document start.
       "\\begin{document}\n\n"
       ;; Subject and title.