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How to Fix Cloudflare 521 Error with Wildcard Subdomains - Nginx Upstream Connection Refused: Causes and Fixes-Fix VS Code Source Control Not Detecting Changes with Permission Denied

Updated 2026-07-28 14:57:15database-tools
How to Fix Cloudflare 521 Error with Wildcard Subdomains - Nginx Upstream Connection Refused: Causes and Fixes-Fix VS Code Source Control Not Detecting Changes with Permission Denied
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.