HTML Header Analyzer

⚠️ Browsers can't read response headers from servers that don't allow cross-origin header access (CORS). The tool will detect that and explain options: (1) use a server-side probe, (2) enable a proxy (experimental), or (3) ask the site owner to allow CORS for headers.
Only enable if you understand privacy tradeoffs. If empty or unchecked, the tool won't use a proxy.