Feature request for GROUPBY=grouplist

Must be the time of year, apologies for adding to 'THE LIST'.

Set GROUPBY=grouplist shows list of groupable columns (visible columns)
and selecting one puts lister in expanded grouped mode, please add a modifier that will group the selected item from the list in collapsed mode.

Set GROUPBY=grouplist
GROUPCOLLAPSE=on

and
Set GROUPBY=grouplist GROUPCOLLAPSE=on

does not work

Sure, we'll add this in the next beta.