After moving our site to another server, a problem occurred. If a page of the site has 'background' code, it is now not possible to edit that page. This error occurs:
'403 Forbidden Access to this resource on the server is denied!'
https://sheki.org/wiki/index.php?title=%C5%9Eablon:15_aprel&action=submit
But after deleting the "background" code on that page, everything is fine. How to solve this problem?