// Per <https://fidoalliance.org/specs/fido-v2.0-id-20180227/fido-appid-and-facets-v2.0-id-20180227.html#determining-the-facetid-of-a-calling-application>:
//
// "In the Web case, the FacetID MUST be the Web Origin [RFC6454]
// of the web page triggering the FIDO operation, written as
// a URI with an empty path. Default ports are omitted and any
// path component is ignored."
//
// This leaves it unclear as to whether the path must be empty,
// or whether it can be non-empty and will be ignored. To be on
// the safe side, use a proper web origin (with empty path).
// Per <https://fidoalliance.org/specs/fido-v2.0-id-20180227/fido-appid-and-facets-v2.0-id-20180227.html#determining-the-facetid-of-a-calling-application>:
//
// "In the Web case, the FacetID MUST be the Web Origin [RFC6454]
// of the web page triggering the FIDO operation, written as
// a URI with an empty path. Default ports are omitted and any
// path component is ignored."
//
// This leaves it unclear as to whether the path must be empty,
// or whether it can be non-empty and will be ignored. To be on
// the safe side, use a proper web origin (with empty path).