List group by (just another option)

[troester]

In list settings every element can be used to group by.
In "Group by" frontend action you can only group by elements shown in list view.

It would be nice to have the possibility to define the "group by" elements (like "Allow ordering") (but out of all elements).
So you could give the user the choice e.g. to "ungroup" and group again without confusing him with a lot of elements (including meaningless ones like id)