I think the suggested workaround doesn't work correctly when the grid has Column Virtualization.

I implemented it for a Grid with Column Virtualization and the first time the user changes the sorting it goes to the Unsorted state, because for some reason the state's SortDescriptors list is empty. After that first time sorting, the workaround works properly.

Not a big deal but wanted to give that info.

Right now I'm fixing it manually with:               

if (desiredState.SortDescriptors.Count == 0)
{

desiredState.SortDescriptors.Add(new SortDescriptor
{
SortDirection = ListSortDirection.Ascending,
Member = DefaultSortColumnName
});

}