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Webflow fix guide

Cross-Origin Isolation Headers Not Configured on Webflow

One or more cross-origin isolation headers (COOP, COEP, CORP) are not set. These headers provide defense-in-depth but are only required if your site uses features like SharedArrayBuffer or needs strict cross-origin isolation.

Issue ID: SEC-CROSS-ORIGIN-ISOLATION-001Severity: advisoryEffort: S

Why this matters

One or more cross-origin isolation headers (COOP, COEP, CORP) are not set. These headers provide defense-in-depth but are only required if your site uses features like SharedArrayBuffer or needs strict cross-origin isolation. This affects browser trust signals and whether visitors feel safe submitting contact details.

Webflow fix path

How to fix this on Webflow

Use page settings, Designer, or project settings.

  1. 1Locate the element or setting causing the issue.
  2. 2Update it in Webflow.
  3. 3Publish and validate the output.

After you fix it

  • ✓Confirm all three cross-origin headers are present in response headers

Same fix, other platforms

Fix cross-origin isolation headers not configured on a different CMS

Other fixes

More Webflow fixes

Parents

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