This code snippet uses jQuery to replace product thumbnail images with their full-size versions in the WordPress admin products list page. It ensures that whenever the page loads or the product list is refreshed, the thumbnails are updated to show larger images.

replace-thumbnails-with-fullsize-images.php

<?php
/**
 * Use jQuery to replace product thumbnails with full-size images in admin
 * @author: Faisal Ahammad
 */
function replace_admin_thumbnails_with_fullsize_js() {
    $screen = get_current_screen();
    if (!$screen || $screen->base !== 'edit' || $screen->post_type !== 'product') {
        return;
    }
    
    ?>
    <script type="text/javascript">
    jQuery(document).ready(function($) {
        // Function to replace thumbnail URLs with full-size URLs
        function replaceWithFullSizeImages() {
            $('.column-thumb img').each(function() {
                var $img = $(this);
                var src = $img.attr('src');
                
                // Remove size suffix from URL (e.g., -150x150.jpg → .jpg)
                var fullSizeSrc = src.replace(/-\d+x\d+(\.[^.]+)$/, '$1');
                
                // Set the new source and remove srcset and sizes
                $img.attr('src', fullSizeSrc)
                    .removeAttr('srcset')
                    .removeAttr('sizes');
            });
        }
        
        // Run initially and also when list is refreshed
        replaceWithFullSizeImages();
        
        $(document).ajaxComplete(function() {
            setTimeout(replaceWithFullSizeImages, 100);
        });
    });
    </script>
    <?php
}

add_action('admin_footer', 'replace_admin_thumbnails_with_fullsize_js');