It is quite a common pragmatic architectural pattern in the HTML architecture. For example, data urls where a MIME type representation is encoded in the URL for

It is quite a common pragmatic architectural pattern in the HTML architecture. For example, data urls where a MIME type representation is encoded in the URL format is used for embedding images and other MIME types. So, if one is building an application and needs to render a proprietary data object, this is a good way (not the only one) to handle it using a client library.