@ -843,6 +843,7 @@ class ProxyingHTTPRequestHandler(http.server.BaseHTTPRequestHandler):
"""Return an HTTP error status and a message in the response body."""
self.send_response(status)
self.send_header("Content-Type", "text/plain; charset=utf-8")
self.end_headers()
self.wfile.write(message.encode("utf-8"))