custom wordpress post loop – hide iframe content

the best solution is to add filter in your functions.php :

add_filter('the_content','show_only_thumbnails',99);

function show_only_thumbnails($content){
    if(is_home() && is_front_page()){
     //quote from :
     //http://wordpress.stackexchange.com/questions/218305/display-only-text-to-wordpress-loop-without-loosing-the-text-formatting/218314#218314
     $content = preg_replace('/<iframe.*?>/', "", $content); // removes iframes
      return $content;
    }
   return $content;
}