reInit breaks tabindex

[dragoss]

Hello,

First of all I want to thank you for your awesome work!
Secondly, I have an issue when I'm trying to dynamically change any of the carousel's options by calling setOption with refresh: true. The result is that tabindex: -1 is removed for all focusable elements in all slick-cloned that are appended at the end, so elements inside the cloned slides can be focused (also the carousel moves and breaks).

I've created an example here. I turned off the autoplay, because if the carousel moves, the issue goes away.

The issue seems to be related to reInit, which does not call updateSlideVisibility.

Thanks in advance!

Regards,
Dragos