The enforce_user_fields prevents Drupal from generating CSS and JavaScript.

After registering a new user via a third-party authenticator (in my case, BankID), the enforce_user_fields setting prevents the generation of JavaScript and CSS.

Here are some error messages from the browser console:

Refused to apply style from 'https://my-site.lndo.site/user/41/edit?destination=/sites/default/files/css/css_5hxjhCN4vBDEaziLG0bXWLCSOjdOXHBhADeoZgM-AiU.css' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.
Refused to execute script from 'https://my-site.lndo.site/user/41/edit?destination=/sites/default/files/js/js_GSzMtZgi6JEtUWWo1j_XpqSFml9S-R4gU-5Zj_Q-A4M.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
Refused to apply style from 'https://my-site.lndo.site/user/41/edit?destination=/sites/default/files/css/css_5hxjhCN4vBDEaziLG0bXWLCSOjdOXHBhADeoZgM-AiU.css' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.