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Fixing Cloudflare 521 Error with Nginx Configuration - VS Code SSH Host Key Verification Failed Fix-Fixing systemd Service File Syntax Errors

2026-06-13 13:39:04developer-tools
Fixing Cloudflare 521 Error with Nginx Configuration - VS Code SSH Host Key Verification Failed Fix-Fixing systemd Service File Syntax Errors

Final checklist

  • Confirm that the same symptom is gone after a restart or refresh.
  • Keep the smallest working change and undo temporary diagnostic settings.