Grid header filter value for boolean column

I have a grid editable column which is of type boolean. I want to implement a filter dropdown in the header which has two options: “Checked state” and “Unchecked state”.

How can i archive this very basic thing?

10x in advance.

Hello.

Unfortunately, currently there is no possibility to define templates for the combo/select filter options. Only the cell values can be used in the options.

How can i archive this behavior with custom cell?

COuld you please, clarify what is a custom cell?
I suppose you may use the template for the cells of your column:
https://docs.dhtmlx.com/suite/grid/customization/#adding-template-to-cells