Hi, 

From form and content type (com_cck&view=type&layout=edit), when I want to save a field or create a new one, the save does not work and the progress bar on the left loops. I then have to leave the field with the "closed" button. 

If I edit the field from the list of fields (com_cck&view=fields), I get an error (403 Forbidden Access to this resource on the server is denied!). 

This result occurs with a test version of the site at the PlanetHoster host and does not concern all the fields, it is random, but always the same. 

Joomla! 3.10.11 
PHP 8.0.28 
Seblod 3.25

This result does not occur at OVH (with same website)
Joomla! 3.10.11 
PHP 8.0.28
Seblod 3.25

Thanks for your help !