How to show a block with an index that matches the index of the active slide?

Question

JavaScript

Greetings.
The task is to show a block whose index corresponds to the index of the central active slide.
There is a slider on the page, it displays 3 active slides. There is a function that adds a class to the central slide .owl-center
. Under the slider there is a block in which blocks with content.
It is necessary to find out the index of the central slide and assign a class to the block with the same index. .active

When trying to find out the index of the central slide, it always returns -1.
Help, please, to understand.

Here is an example: https://codepen.io/OculusDaemon/pen/vVWmOR

PS I am using owl-carousel with the valueloop: false

Answer 1

here