Explain

COOP (Cross-Origin-Opener-Policy)

Controls whether your top-level page shares a browsing context group with cross-origin documents (security/isolation).

InfoCategory: headers
What it is

COOP helps isolate your page from cross-origin windows/tabs to reduce cross-origin attacks and enable stronger isolation.

Common values
  • same-origin (strict)
  • same-origin-allow-popups (less strict)
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