[Visible binding/Runtime.js] Range Slider Widget Extension

Hey!

I am using the marketplace's Range Slider extension which set as invisible in a mashup. Upon some data filled on the mashup the binding property of the widget "Visible" is set to true. The widget shows but its pickers appear on weird places (badly rendered).

Once I set one of its properties the widget is rendered properly.

If the widget is loaded as visible it is rendered properly too.

So I need to change the extension but I cannot figure how the binding for the visibility is set in the runtime.js. I am not a pro to jquery and html.

Could you help me?

Thanks in advance