is_ssl() Breaks on Non-Standard HTTPS Port

[404e]

The WordPress is_ssl() function incorrectly fails to detect an SSL connection when a site uses a non-standard HTTPS port (e.g., 3443 instead of 443). The issue lies with the specific line of code that checks ( '443' === (string) $_SERVERSERVER_PORT? ).

This flawed logic causes SSL-dependent functionality to break, including leading to redirect loops in the /wp-admin/ dashboard. After removing this specific port check from the function, my site's SSL detection works correctly and the redirect loop is resolved.

[westonruter]

Hello!

I think this is why ​the function also checks for the $_SERVER['HTTPS'] is true or 'on'.

Just make sure that you set this variable and the function will work as desired. You can manually set it in your wp-config.php if need be. Does this work?