adding many tabs - the arrow to scroll not appear correct

Our system allows users to add many tabs(unlimited). When the number of tabs get to a certain number, the arrow to scroll left and right appears. However(see the attached image), the right arrow scroll seems to jump around and not appearing at the end of the list.

Please advise.
Thank you.


are you using the latest version ? Try the latest if you are not and attach the complete demo if the problem occurs in the 3.0 version