This happens on my website, but it also happens on the foundation website itself. You need two clicks a few seconds apart if you click a menu tab that has a dropdown. You can see an example here:

https://gyazo.com/3a9af8cb54fe75008c7ecc96e701d035

I hover over showcase, click once, I get nothing. One second later I click again and it takes me to "show case" is this behaviour intended? 

Is there any way to turn this off?