Double scrollbars

Hi

After the recent WordPress update I noticed a problem: in Google Chrome there appear 2 scrollbars. When you click on the “nee”-button and want to scroll you get a scrollbar that is not working well (wont go down). You have to move to the right side of the popup to get the normal scrollbar so you can scroll to the bottom.

I tested it in Firefox en Safari but there it works fine. Only in Chrome this problem occur.

Something I can do to get rid of this problem?

Thanks in advance

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