Nginx proxy not able to display squirrelmail

Running Nginx as a reverse proxy, webmail like Horde and Squirrelmail fail to display Because of the webmail.php use header as below i.imgur.com/SyVyI8t.png i.imgur.com/p8lbeZr.png This popped up in a recent upgrade I believe Ref: github.com/engintron/engintron/issues/864 Webmail not working " Issue #864 " engintron/engintron