- Replace postMessage wildcard ('*') with explicit parent origin passed
via ?origin= parameter to prevent auth state disclosure to arbitrary
embedders
- Tighten frame-ancestors CSP: production restricts to self + DOMAIN,
dev restricts to localhost origins (was frame-ancestors *)
- Remove deprecated X-Frame-Options ALLOW-FROM header (CSP
frame-ancestors is the modern replacement)
- Validate targetOrigin with URL constructor before use
Bunker Admin