According to the documentation for the ComboBox, https://www.telerik.com/blazor-ui/documentation/components/combobox/filter, "Filtering looks in the TextField, and the filter is reset when the dropdown closes."

However, if the user starts typing and then either selects an item from the dropdown, the filter persists until the user clears the text box or opens the dropdown and clicks outside of it.

Example steps using the below demo link:

1.) Configure settings:


2.) Type the letter 'h':


3.) Select the first option:

4.) Click dropdown arrow and still see filtered list based on the previously typed filter (anything containing an 'h'):



Reproducible on the demo page: https://demos.telerik.com/blazor-ui/combobox/filtering

The matching problem occurs when a user types to filter input and selects an option from the dropdown, then code changes the bound value. If any code changes the bound value to an item that doesn't match the filter, the display field appears empty instead of showing the newly bound value.

For example: if instead of opening the dropdown during step 4, the user clicked a button that programmatically set the value to "Audi", then the field would show to the user as blank. As demonstrated in the following Repl, it is definitely the filters fault, since typing a filter which includes Audi (ex: 'a') does have the text on the ComboBox change when clicking the button to programmatically update the bound value.

https://blazorrepl.telerik.com/cJapEQGO21LFAeLg53