Ok, please find them in private content. Thank you.

Thank you, I did what you said, but the change has no effect, it doesnt add the class.
Here is the code that I added to my childtheme’s functions.php

    function etheme_create_slider($args, $slider_args = array()){//, $title = false, $shop_link = true, $slider_type = false, $items = '[[0, 1], [479,2], [619,2], [768,4],  [1200, 4], [1600, 4]]', $style = 'default'
        global $wpdb, $woocommerce_loop;
        
        $product_per_row = etheme_get_option('prodcuts_per_row');
        extract(shortcode_atts(array( 
	        'title' => false,
	        'shop_link' => false,
	        'slider_type' => false,
	        'items' => '[[0, 1], [479,2], [619,2], [768,4],  [1200, 4], [1600, 4]]',
	        'style' => 'default',
	        'block_id' => false
	    ), $slider_args));

        $box_id = rand(1000,10000);
        $multislides = new WP_Query( $args );
        $shop_url = get_permalink(woocommerce_get_page_id('shop'));
        $class = $container_class = $title_output = '';
        if(!$slider_type) {
        	$woocommerce_loop['lazy-load'] = true;
        	$woocommerce_loop['style'] = $style;
        }
        

        if(!$slider_type) {
            $container_class = '';
            $class .= 'owl-carousel';
        } elseif($slider_type == 'swiper') {
            $container_class = 'et-swiper-container';
            $class .= 'swiper-wrapper';
        }

        if ( $multislides->have_posts() ) :
            if ($title) {
                $title_output = '<h2 class="title"><span>'.$title.'</span></h2>';
            }   
              echo '<div class="carousel-area '.$container_class.' slider-'.$box_id.'">';
                  echo $title_output;
                  echo '<div class="'.$class.' productCarousel">';
                        $_i=0;
                    	if($block_id && $block_id != '' && et_get_block($block_id) != '') {
                            echo '<div class="slide-item '.$slider_type.'-slide">';
                                echo et_get_block($block_id);
                            echo '</div><!-- slide-item -->';
                    	}
                        while ($multislides->have_posts()) : $multislides->the_post();
                            $_i++;
                            $first_slide_class = ( $_i === 1 ) ? 'your-first-slide-class' : '';
                            if(class_exists('Woocommerce')) {
                                global $product;
                                if (!$product->is_visible()) continue; 
                                echo '<div class="slide-item product-slide '.$slider_type.'-slide">';
                                    woocommerce_get_template_part( 'content', 'product-slider' );
                                echo '</div><!-- slide-item -->';
                            }

                        endwhile; 
                  echo '</div><!-- products-slider -->'; 
              echo '</div><!-- slider-container -->'; 
        endif;
        wp_reset_query();
        unset($woocommerce_loop['lazy-load']);
        unset($woocommerce_loop['style']);
        
        if($items != '[[0, 1], [479,2], [619,2], [768,4],  [1200, 4], [1600, 4]]') {
            $items = '[[0, '.$items['phones'].'], [479,'.$items['tablet'].'], [619,'.$items['tablet'].'], [768,'.$items['tablet'].'],  [1200, '.$items['notebook'].'], [1600, '.$items['desktop'].']]';
        } 
        if(!$slider_type) {
	        echo '
	
	            <script type="text/javascript">
	                jQuery(".slider-'.$box_id.' .productCarousel").owlCarousel({
	                    items:4, 
	                    lazyLoad : true,
	                    navigation: true,
	                    navigationText:false,
	                    rewindNav: false,
	                    itemsCustom: '.$items.'
	                });
	
	            </script>
	        ';
        } elseif($slider_type == 'swiper') {
	        echo '
                <script type="text/javascript">
                  if(jQuery(window).width() > 767) {
                      jQuery(".slider-'.$box_id.'").etFullWidth();
                      var mySwiper'.$box_id.' = new Swiper(".slider-'.$box_id.'",{
                        keyboardControl: true,
                        centeredSlides: true,
                        calculateHeight : true,
                        slidesPerView: "auto",
                        mode: "horizontal"
                      })
                  } else {
                      var mySwiper'.$box_id.' = new Swiper(".slider-'.$box_id.'",{
                        calculateHeight : true
                      })
                  }
                
                    jQuery(function($){
                        $(".slider-'.$box_id.' .slide-item").click(function(){
                            mySwiper'.$box_id.'.swipeTo($(this).index());
                            $(".lookbook-index").removeClass("active");
                            $(this).addClass("active");
                        });
                        
                        $(".slider-'.$box_id.' .slide-item a").click(function(e){
                            if($(this).parents(".swiper-slide-active").length < 1) {
                                e.preventDefault();
                            }
                        });
                    }, jQuery);
                </script>
	        ';
        }
            
    }

Or do you mean that I should use the ids that are automatically generated like slider-8637?
Thats no solution as I need these sliders on every product page…

No, it’s very confusing.
If I add the shortcode [etheme_products] to a page, classes are set like this:
1. Item class FIRST
2. Item
3. Item
4. Item class LAST
5. Item class FIRST
[…]

But if I add the same shortcode on product description field of a product, the classes are set like this:
1. Item
2. Item
3. Item class LAST
4. Item class FIRST
5. Item
[…]

When I add two shortcodes like [etheme_products][etheme_products], the first slider has the classes set like my second example and the second slider has the classes set like the first example.

I really don’t get it, its totally confusing. I would like to ignore all of these confusing classes and just find a way to style the first item of the slider, but I dont know how. :first-child doesnt work here…

Thank you, but I don’t want to use grid, I want to use slider…

I think I found the part that causes the problem:
In content-product-slider.php there is this part:

// Extra post classes
$classes = '';
if ( 0 == ( $woocommerce_loop['loop'] - 1 ) % $woocommerce_loop['columns'] || 1 == $woocommerce_loop['columns'] )
	$classes .= 'first ';
if ( 0 == $woocommerce_loop['loop'] % $woocommerce_loop['columns'] )
	$classes .= 'last ';

When I edit it to the following, it seems to work but I dont know if this is a proper solution or if this will cause any problems…?

// Extra post classes
$classes = '';
if ( 0 == ( $woocommerce_loop['loop'] - 1 ) )
	$classes .= 'first ';
if ( 0 == $woocommerce_loop['loop'] % $woocommerce_loop['columns'] )
	$classes .= 'last ';

Hello Eva,
thank you but that doesnt solve my problem. I want to automatically show all products with a specific tag on single product pages but exclude the current product. An alternative solution would be to reorder the results and always show the current product as first slide, but I think this would be even more complicated…

Yes I know but I dont want to add to many template files into my childtheme. I always prefer to use functions.php of my childtheme for modifications. So, isn’t there a way to achieve this via functions.php?

Ok I could solve it. It’s too complicated to explain in detail but it had something to do with YOAST seo plugin and breadcrumbs (your modification in etheme grabs the product title from a part in breadcrumbs and not just from the product-title, that makes it a bit complicated when using custom breadcrumbs). Sorry that I thought it was not fixed!

Hello Eva,
the screenshot Jack posted (and now deleted – thank you) was taken from my official page, where I still have version 2.7.3 enabled. I uploaded the new version 2.8. to a test environment. Before I give you FTP credentials, let me tell you what I changed to make it work:
In etheme.js line 1470, there is:

if ($('.product_title').first().text()) {
 productName = $('.product_title').first().text();
 } else {
 productName = $('h1.title').first().text();
 }

and I changed the code to:

if ($('.meta-title span').first().text()) {
 productName = $('.meta-title span').first().text();
 } else {
 productName = $('h1.title').first().text();
 }

Is it possible that the problem was only fixed for simple products? I have only variable products so I can not check it but maybe you can..

It’s still not fixed in version 2.8. Why??

Thanks. I know that I can customize the theme using my childtheme. I just wanted to know if the specific change I made (adding the “products” class to the string in loop-start.php) could cause any problems?

The changelog of verison 2.7.3 says that this is fixed, but I just updated and the bug is still there :/

Ok thank you! Looking forward for the fix!