How to display the previous article when assigned to a postal page?

Please tell me how to display a pop-up window with a preview inside the article when hovering over a link. I think this is a very usability thing and many will be interested in its implementation. Found this code (illegal), how to make it work? .single.content - I guess the text wrapper and the script looks for a link in it and loads the article preview (hrefcontent) on hover.

1

Guys, please tell me how to attach a callback to this script and make the pop-up work? Block pops up empty yet (link)

all I could do was display the script and display a popup on hover, I can’t fill the popup with data from the article via the link

/* hovering over links in an article */
  $('.entry-content .cherry-block p a').hover(
    function(){
      if ($(this).attr('href') && !$(this).hasClass('load')&& !$(this).hasClass('loaded')){
        $(this).addClass('load');
        $(this).html($(this).html()+'<div class="hrefcontent"><div><img src=""></div><h4></h4>'+'<p>Здесь будет превью</p></div>');

        var data = {action: 'post_href',href: $(this).attr('href')};
        $.post("<?php echo admin_url( 'admin-ajax.php'); ?>", data, function(response) {
          if(response.title!=''){
            $('.entry-content .cherry-block p a.load').find('h4').html(response.title);
            $('.entry-content .cherry-block p a.load').find('p').html(response.description);
            $('.entry-content .cherry-block p a.load').find('img').attr('src',response.img);
            $('.entry-content .cherry-block p a.load').addClass('loaded').removeClass('load');  
          } else
            $('.entry-content .cherry-block p a.load').find('.hrefcontent').remove();

        }, 'json');
      }
      if($(this).hasClass('loaded') && $(this).find('.hrefcontent') )   {
        $(this).find('.hrefcontent').show();
      }
    },
    function(){
      $(this).find('.hrefcontent').hide();
    });

}); // jQuery End
</script> 
  <?php
}
add_action('wp_footer', 'my_custom_ajax');
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