diff -up evolution-3.8.5/modules/settings/e-settings-mail-formatter.c.crash-mail-header-show evolution-3.8.5/modules/settings/e-settings-mail-formatter.c

--- evolution-3.8.5/modules/settings/e-settings-mail-formatter.c.crash-mail-header-show	2014-08-25 17:24:50.317186665 +0200

+++ evolution-3.8.5/modules/settings/e-settings-mail-formatter.c	2014-08-25 17:24:50.323186664 +0200

@@ -67,13 +67,13 @@ settings_mail_formatter_headers_changed_

 	if (key) {

 		GSList *link;

-		for (ii = 0, link = extension->priv->old_headers; headers && headers[ii]; ii++, link = g_slist_next (link)) {

+		for (ii = 0, link = extension->priv->old_headers; link && headers && headers[ii]; ii++, link = g_slist_next (link)) {

 			if (g_strcmp0 (link->data, headers[ii]) != 0)

 				break;

 		}

 		/* both lists are read to the end, thus they are the same */

-		if (!headers[ii] && !link) {

+		if ((!headers || !headers[ii]) && !link) {

 			g_strfreev (headers);

 			return;

 		}