Slider resizing and selection issues

Claus Due reported an issue

Resizing the slider results in an odd and slow/heavy rendering, and clicking the navigation items ignores second click if an animation is running (see video)

Reported URL:https://new.typo3.org/

User Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36