Horizon Analytics - Row Grouping on String Field is being restricted as there is a Rick Text Area field added to the report

Hello Team, 

I can see that the legacy Analytics system allowed us to add Row Grouping on a string field and we could have a Rich Text Area field added in the report. Please refer to the attached screenshot. But, in Horizon Analytics this feature is not working. When I enabled Row Grouping on a String field, and the report has a Rich Text Area field I am facing an error saying that "Aggregation functions are not allowed on field(s) Description for RICHTEXTAREA datatype”. The same functionality was working in the legacy Analytics System. 

Is this feature intentionally disabled in Horizon Analytics or is there something I am missing.