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Cloudflare 521 Error After Update: Fixes That Work - Troubleshooting Go Proxy Connection Refused on Setup-WSL Ubuntu resolv.conf Keeps Resetting Fix

Updated 2026-06-13 15:23:40browser-issues
Cloudflare 521 Error After Update: Fixes That Work - Troubleshooting Go Proxy Connection Refused on Setup-WSL Ubuntu resolv.conf Keeps Resetting Fix
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.