In radgrid, when you are filtering the grid using EXCEL like filtering, you get a Listbox where you can enter a filter string, which then shows a filterlist of checkboxes that match that filter string.  There is a checkall checkbox at the very top.  If you select that, it selects all the filtered list checkboxes and checks them.

When you then click the filter button to apply the selection, the filter criteria is ignored, and no grid filtering occurs.

I did find a "fix" for this, but it is not useable.  

https://www.telerik.com/support/code-library/make-check-all-to-include-only-displayed-list-options-in-excel-like-filtering

The problem with this fix is that it works on the first applied filter, but if you the try to filter again, the Listbox takes a extremely long time to load the checkbox list, and so is not practical.

Is there a better solution?  Has this even been identified as a bug which will be fixed?