Hi,

I would like checkbox support including the check all checkbox on the multiselect component like: https://docs.telerik.com/devtools/aspnet-ajax/controls/combobox/functionality/checkbox-support

The url below shows how to create custom checkboxes in the multiselect component but adding a check all checkbox in the headertemplate does not update the multiselect popup

https://docs.telerik.com/blazor-ui/knowledge-base/multiselect-checkbox-in-dropdown?_ga=2.50111909.206897922.1631541466-694624900.1630583797&_gac=1.246637872.1631604077.EAIaIQobChMI8PnX6Pb98gIVkwCLCh381AjMEAAYASAAEgLROPD_BwE