Menu bar keeps repeating after clicking a tablink

Thanks to the new update my quantity text in the cart is now visible :).

But I found out something else. If you click on a tab of the menu bar, you will see a glimpse of that same menu bar arranged vertically, which disappears as soon as the page is loaded. This seems to be a bug in the site. Have you got any ideas as to what might cause this problem and how it can be solved?

The bug seemed to occur most often when we clicked on the ‘Algemene Voorwaarden’ tab.

We thank you in advance for any help you can give us.

my site: https://www.camerahulpstuk.nl