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Chrome Extensions Not Loading? Troubleshooting Checklist - Resolve Windows Defender Port Allocation Error-Cloudflare 521 Error: Causes and Fixes

Updated 2026-06-13 12:47:44developer-tools
Chrome Extensions Not Loading? Troubleshooting Checklist - Resolve Windows Defender Port Allocation Error-Cloudflare 521 Error: Causes and Fixes
Likely symptom
Likely cause
Safe rollback

Verification route

  • Repeat the original action, not only a simplified test case.
  • Restart the app or reload the service after configuration changes.