onChange() dont work with tabs

in the API documentation i can see that tabs have the onChange event handler, But when i am adding it in my code i get an error, i am doing it wrong ?

I tested in the classic editor in a site of mine and was not able to recreate this issue so this appears to be a bug with your editor as even the events panel on the right hand side is not showing the onChange(). You will want to report the bug through support as there is no customer care presence in the forum here.