Read more / less in category text

Hey KvarngardenMedia,

Thank you for the inquiry.

Try to add this script in the functions.php file to initially hide some of the categories and create a toggle button.

function ava_add_custom_script(){
	?>
	<script>
	(function($) {
		$(".product_meta").prepend("<a class='prod_category_toggle cat_hidden' href='#'>toggle</a>");

		$(".prod_category_toggle").on("click", function() {
			var toggle = $(this);
			
			if( toggle.is(".cat_hidden") ) {
				show_categories(); 
			} else {
				hide_categories(); 
			}

			toggle.toggleClass("cat_hidden");
		});

		function hide_categories() {
			var posted_in = $(".product_meta .posted_in").html();
			var posted_in_replaced = posted_in.replaceAll(", ", "<span class='sep'>, </span>");
			
			$(".product_meta .posted_in").html(posted_in_replaced);
		
			$(".product_meta .posted_in a").each(function(i) {
				if (i > 10) {
					$(this).css("display", "none");
					$(this).next(".sep").css("display", "none");
				}
			});
		}

		function show_categories() {
			$(".product_meta .posted_in a").each(function(i) {
				$(this).css("display", "inline");
				$(this).next(".sep").css("display", "inline");
			});
		}

		hide_categories();
	})(jQuery);
	</script>
	<?php
}
add_action('wp_footer', 'ava_add_custom_script');

You can adjust the style of the toggle button with this css code.

.prod_category_toggle {
    position: absolute;
    background: #555555;
    padding: 10px 15px;
    font-size: 15px;
    border-radius: 2px;
    color: #ffffff;
}

Best regards,
Ismael