gibarra
Hi
403 error is from server side, On your site there is Admin Tools extension that blocking the access.
Kindly disable it and check http://prntscr.com/18mzp83
You can report it to Extension provider it might need changes in the extension settings.
For PHP 8 i shared the issue with dev team member. But again your site has htaccess login and wee are unable to login on backend.
Kindly fix the access. We are not able to replicate the same issue on PHP 8.
You can try this file
administrator\components\com_community\views\themeprofile\tmpl\info.php
