We are not aware of such a problem and you're the first to report it.
Are you able to reproduce the problem in the live demos
of the component, which run the latest R3'16 ver 2016.3 914?
If the problem is not reproducible you can compare your code with the one of the demo and see the differences as well as to update to the latest version 2016.3 914 of the widget to make sure it's up to date.
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