Reverse proxy causes issue with CSS links and HTTPS I have multiple Drupal instances behind a F5 load balancer. If I use it as http, that is OK. If I want to use http and https and ofload https on the LB, all CSS and JavaScript links in the https site comes as http and cannot be loaded because of the https security.
Do you have any css/js aggregation module installed. If so delete the caches under sites directory. You can even try uninstalling the module to debug if that is causing the issue.
Clear Drupal caches
Ensure you do not have global $base_url hard coded to http.