Checklists for software errors, setup, and tool workflows.

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Latest checklists

You changed your SSL/TLS setting in Cloudflare (for example, from Flexible to Full or Full Strict...

When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Fix Chrome Certificate Error Invalid Authority on Mac
You're browsing in Chrome on a Mac and suddenly see a warning: Your connection is not...

How to Fix Edge Sync Not Working on Windows 11
If your Microsoft Edge browser has stopped syncing bookmarks, passwords, or settings across devic...

Fix Git 'index.lock file exists' Error
If you see fatal: Unable to create 'path/.git/index.lock': File exists. when...

VS Code Git Not Detecting Changes: Step-by-Step Fix
You've edited files in VS Code, but the Source Control panel shows no changes. The git icon m...