Just wanted to add a quick way to scan for plugins that use pluggable.
Use the following linux command in the wp root directory (or change . to /path/)
find ./wp-content -name \*.php | xargs grep "/pluggable.php"
You’ll get a list of all plugins using pluggable.php
./wp-content/plugins/automatic-domain-changer/auto-domain-change.php: require_once(ABSPATH .’wp-includes/pluggable.php’);
In my case it was only Automatic Domain Changer that used it and caused it.
Disabled it and it worked fine.
Thanks eveyone!
