From 033189dc42d8d6a90fb24510f6a3cf3bd1555e3e Mon Sep 17 00:00:00 2001
From: Jamie Cameron <jcameron@webmin.com>
Date: Mon, 27 Jun 2022 23:03:29 -0700
Subject: [PATCH] Handle case where substitution doesn't exist

---
 postfix/postfix-lib.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/postfix/postfix-lib.pl b/postfix/postfix-lib.pl
index 807eb6913..e1418d50d 100755
--- a/postfix/postfix-lib.pl
+++ b/postfix/postfix-lib.pl
@@ -1551,7 +1551,7 @@ if ($postfix_version >= 2.1 && $v =~ /\$/) {
 		return $out;
 		}
 	}
-$v =~ s/\$(\{([^\}]+)\}|([A-Za-z0-9\.\-\_]+))/get_real_value($2 || $3)/ge;
+$v =~ s/\$(\{([^\}]+)\}|([A-Za-z0-9\.\-\_]+))/get_real_value($2 || $3) || '$'.$1/ge;
 return $v;
 }