diff --git a/src/fe-text/textbuffer-reformat.c b/src/fe-text/textbuffer-reformat.c
index d719c468..9bccbc5a 100644
--- a/src/fe-text/textbuffer-reformat.c
+++ b/src/fe-text/textbuffer-reformat.c
@@ -228,7 +228,8 @@ static void sig_print_format(THEME_REC *theme, const char *module,
 		g_string_append_c(format, '\0');
 		g_string_append_c(format, (char)LINE_CMD_FORMAT);
 
-		g_string_append(format, args[n]);
+		if (args[n] != NULL)
+			g_string_append(format, args[n]);
 	}
 }