MW 1.34, PF 5.0
A form contains a datepicker field that is mandatory and only shown per a "show on select" from another field.
This produces a JS error that is easily seen in the developers console. The error is due to the JS not being able to 'focus' on the hidden field and trying to do so because it is mandatory.
The user experience is that the save button for the form does nothing.
/Rich