The dialog to configure the CUPS server HTTP settings is shown here.
CUPS server HTTP settings are the following ones:
The root directory for HTTP documents that are served. By default the compiled in directory, /usr/share/cups/doc
The default language, if not specified by the browser. If not specified, the current locale is used.
The default character set to use. If not specified, this defaults to UTF-8. This can also be overridden directly in the HTML documents.