ReDHumus Web  Help: /.well-known

The "/.well-known" page:

If the "--acme" option was supplied to "fossil server" or "fossil http" or similar, then this page returns the content of files found in the ".well-known" subdirectory of the same directory that contains the repository file. This facilitates Automated Certificate Management using tools like "certbot".

The content is returned directly, without any interpretation, using a generic mimetype.