I'm having issues using jQuery 3 with the carousel widget. I had to downgrade to jQuery v2 in order for the widget to work as expected. I'm not sure if it's all the widgets or just this one.
Looking into this, I found the OwlCarousel library is at ver 2.0.0. Updating to 2.3.4 fixes the problem, although, some functionality is lost like navigation. My guess is the HTML and JS options need to be updated too.