I´ve set the width down to 1% in style.css
Its a workaround. Is there a better solution?
THX
/* ———– Single Post Styling ———— */
.single img.featured {
margin-bottom: 20px;
width: 1%;
-webkit-transform: none !important;
-moz-transform: none !important;
-ms-transform: none !important;
transform: none !important; }
.single .featured-slider-container {
margin-bottom: 40px; }
.single .thumbnail-slider-container {
margin-bottom: 20px; }