public Task ClearAllFrozenFieldsAsync()

var tv = TableView.Active;
if (tv == null)
  return;

// get list of frozen fields
var frozenfields = tv.GetFrozenFields();

// un freeze all fields
await tv.ClearAllFrozenFieldsAsync();


// freeze a set of fields
await tv.SetFrozenFieldsAsync(new List<string> { "CITY_FIPS", "STATE_FIPS" });