1. Open Settings › Advanced. On the display Mac, open Settings with the gear on its waiting screen.

  2. Click Export Diagnostics… and save the file.

  3. Attach it to an email to support, with a few words about what happened and when.

The file contains the app’s logs and crash reports, your settings, the names of your Macs and the last speed test. It never contains your screen or your sign-in, and it stays on your Mac until you send it.

Show Logs in Finder, in the same place, opens the folder with the logs.