In Web App Builder, it is frustrating the Group Filter widget does not have the same expression capabilities as the Filter widget. Please make the same or at least support the same capabilities.
The filter widget operators appears to be context specific to field data types where as the Group Filter seems to be applying a generic set of operators.
For example for dates there is no "is between" expression in Group Filter which exists in Filter. So if there are a number of layers which need to be filtered by a date range & unique value it is impossible unless you add multiple Filter widget which confused the end-user and results in a bad user experience.
Other examples for string fields include "is blank" or "is not blank"
Thanks for this consideration