Safari, widget is jumpy while scrolling

I looked through the other threads here and didn’t find a solution to my particular problem but I might have just missed it. Anyway, the widget works great on my site on all browsers except for safari in which as I scroll up and down the widgets are jumpy (they return to form once you stop scrolling).

Is there anyway to stop this?

Thank you.

https://wordpress.org/plugins/q2w3-fixed-widget/