Seen in labs when running a MediaWiki-Vagrant configured wiki behind yuviproxy. Configuration sets $wgServer = WebRequest::detectServer() which works great when HTTP_X_FORWARDED_PROTO is unset or http. When it is https, detectServer() adds ":80" to the generated url (eg "https://sulfinalization.wmflabs.org:80").
This is caused by a mismatch between the standard port for https (443) and the active SERVER_PORT reported by Apache (80). detectServer() calls IP::combineHostAndPort( $host, $port=80, $stdPort=443 ) which leads to a return value of $host:80 since the active port and the default port do not match.
I think naively that this could be fixed by choosing to set $port = $stdPort when $_SERVER['HTTP_X_FORWARDED_PROTO'] is set to 'https' and assume the upstream ssl proxy is running on the standard port 443.
Can anyone think of a realistic deployment scenario where this would be the wrong behavior?