Why does the leftmost image in the slider "merge" when scrolling?

Question

JavaScript

Initially, all the pictures are in place. As soon as I start to turn the slider, the left side of the picture disappears. How to make it stay?
Site - shopper.surge.sh
And another offtopic question (because it is blocked separately)

spoiler

evaluate the layout, if not difficult( code )

Answer 1

here 's what the markup looks like right after the page loads, and here 's what it looks like after the first click to the right. and now look at what happens in the slider code on your plugin page