Did I find a bug?
Repro Steps:
Run the "KendoReact Scheduler Demo Preview" demo from https://www.telerik.com/kendo-react-ui/components/scheduler/#toc-kendoreact-scheduler-demo-preview in StackBlitz (to gain easy access to the JavaScript console).
Run the app in a new window (to gain easier access to the JavaScript console).
Open your browser's developer tools to view the JavaScript console.
In the top left corner, to the right of the "today", "<", and ">" buttons, click the date to open the calendar.
Select a different day from the calendar.
Result:
Calendar closes, and Scheduler navigates to the new day.
Expected:
No error messages.
Actual:
In FireFox, I see this: