"error validating fields"

[DifferentComputers]

I'm on Indigo 2023.1 and after installing the plugin, the initial config dialog will not close. Instead, it says "Error validating fields. Hover over the red field labels above to see the error reason."

There is no red label, and I'm using default values--though I have tried changing them to see if there's an issue, and no diff.

[DifferentComputers]

Canceling the config does let you start using the plugin though.