"Jump" on mobile slider

Good morning,
I'm using one of your basic sliders:

<section id="slider" class="slider-element force-full-screen full-screen">
  <div class="force-full-screen full-screen dark" style="background-image: url('/pathtomyimage');background-position: 50% 0;">
    <div class="container clearfix">
      <div class="slider-caption slider-caption-center">
        <h2 class="title-home" data-animate="fadeInDown">Title</h2>
        <p class="d-none d-sm-block" data-animate="fadeInUp" data-delay="400">Text</p>
      </div>
    </div>
  </div>
</section>

Everything seems to work fine but I notice something strange about the mobile version.
It seems that the slider enlarges by itself when scrolling down.
I already tried to delete the SEMICOLON.documentOnResize > init: function() Function Block in the js/functions.js like you said on other posts but that do not help.
I leave you the address of the site:

Website : http://test-canvas.tk/

Best
S