CONSOLE ERROR: line 387: Mixed Content: The page at 'https://web-platform.test:8444/mixed-content/websocket-request/no-opt-in/same-host-ws/top-level/swap-scheme-redirect/blockable/ws-downgrade-blocks.https.html' was loaded over HTTPS, but attempted to connect to the insecure WebSocket endpoint 'ws://web-platform.test:9001/stash_responder?redirection=swap-scheme-redirect&action=purge&key=4bef3c12-3584-45cb-a416-6fc6a978ddc4&path=%2Fmixed-content&content_type=application/json'. This request has been blocked; this endpoint must be available over WSS.
