I have attached a simplified version of my app that reproduces the issue of infinite valueMapper requests.
This is reproducible in both Edge and Chrome browsers.
Thank you for your help,
Working dojo example to reproduce: https://dojo.telerik.com/aMEKuzex/2
If you set the contents of the combobox using the text() method, pressing the "X" inside the ComboBox will not fire a change event.
If you set the contents of the box using the value() method, or through the UI itself, clearing it afterwards does fire the change event, which is the expected behaviour.