/etc/ufw/applications.d/squid3 is in squid3 3.3.8-1ubuntu6.11.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | [Squid]
title=Squid proxy cache
description=Internet object cache (WWW proxy cache)
ports=2048,3128,3130,3401,4827/tcp
|