All modules (except ("Auto Login From WHMCS) support WHMCS v8. Since the release of the WHMCS v8 beta version we are checking if our modules needs adjustments.
Auto Login From Mails
The "Auto Login From Mails" addon is currently not compatible with WHMCS v8 . A bug in WHMCS prevents releasing an updated version. We have contacted WHMCS and are working on a solution.