Saxon

When Saxon does its own URI dereferencing using the ResourceLoader class, and the HTTP request delivers a 301 response, access is retried using the URI contained in the location field of the HTTP response header. This fails if the location supplied is a relative URI rather than an absolute URI. It should be resolved against the request URI.

For example, a request to https://www.saxonica.com returns a 301 response with location=/index.html, and the next request should be to https://www.saxonica.com/index.html.