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Saturday, October 3, 2020

Apple really sucks at Thunderbolt 3, apparently

There's a small update in the ongoing 2020 Macbook Thunderbolt 3 crash saga today. Someone posted a repro case to the Apple forums (which are normally useless), and this repro case works!

It goes like this. If you have a 2020 MBP or MBA and a Thunderbolt 3 dock or monitor with USB, give it a try. It should crash all by itself at the end.

  1. Reboot the machine for a clean slate. Keep the lid open. Log in.
  2. Connect the TB3 device.
  3. Put it to sleep from the Apple menu.
  4. Wake it up with the USB mouse.
  5. Put it to sleep from the Apple menu again.
  6. Disconnect the TB3 device.
  7. Connect the TB3 device again.
  8. Try to wake it with the USB mouse. If it works, go back to step 5. You might have to wait longer between steps. Once it fails to wake from the USB mouse, wake it up from the built-in keyboard/trackpad and go to the next step.
  9. Put it to sleep from the Apple menu one more time.
  10. Disconnect the TB3 device.
  11. It should crash by itself.

A while later, it'll say something like "your machine was shut down due to a problem", and when you log in after that, you'll get the crash reporter with no stack trace or anything much to add in the bottom half.

Feel free to point them at this post in your report.

Does anyone feel like masking up and braving an Apple store that has a TB3 monitor or dock for sale on the floor near a MBP or MBA? You should be able to reproduce this in under five minutes. Being able to arbitrarily crash their machines using nothing more than what's on the sales floor and actions that are supposed to "just work" should leave a decent-sized impression on them.


October 16, 2020: This post has an update.