Re: "Group by" indicator in column listyes, that's really important!
The group by option is so helpful -
but also soooo dangerous
... when you forget one column with activated group by - don't double check the formula again (otherwise wasting half of the speed benefit of the group by functionality
- and don't notice te additional group by it in the column heading because it's just the "..." in Mean[Column A][Column B ...
So, thumbs up for this wish !!
"Group by" indicator in column listWhen using the New Formula Column option at the top of the data table to group by a categorical column, it would be helpful to use an icon to label a column that "grouping by" has been activated, similar to how columns are labeled as value colors/markers, formula, hidden, excluded, etc.

User InterfaceRe: "Group by" indicator in column list - Status changed to: AcknowledgedHi @amccusker, thank you for your suggestion! We have captured your request and will take it under consideration.
Re: "Group by" indicator in column list - Status changed to: InvestigatingRe: "Group by" indicator in column list - Status changed to: Acknowledged