From Google Drive to Syncthing over Tailscale

I used Dropbox for decades, then switched to Google Drive. Both worked for most of my files. One file never fit, though: my KeePass password database. It’s the file I need on every device and the file I want to keep private the most. After one annoyance too many, I moved it to Syncthing over Tailscale. The rest stays on Google Drive, for now. This post describes why and how. The file that made me care My password manager is KeePass-based.