CONSOLE ERROR: Mixed Content: The page at 'https://web-platform.test:8444/mixed-content/picture-tag/http-csp/cross-origin-http/top-level/keep-scheme-redirect/blockable/opt-in-blocks.https.html' was loaded over HTTPS, but requested an insecure image 'http://www1.web-platform.test:8001/mixed-content/generic/expect.py?redirection=keep-scheme-redirect&action=purge&key=4dc0904a-9514-4c47-91c2-9ab8e61e3611&path=%2Fmixed-content&content_type=image/png'. This request has been blocked; the content must be served over HTTPS.
