<!-- Кнопка изменения расположения постов -->
<style>
.reverse-button {cursor: pointer;}
.reverse-ok {
  display: flex;
  flex-direction: column-reverse;
}
</style>
<script>
$("#pun-viewtopic .postlink").append("<button class='reverse-button'>Изменить расположение постов</button>");
 
$('.topic').toggleClass(localStorage.toggled);
 
/* Toggle */
$('.reverse-button').on('click',function(){
 
   if (localStorage.toggled != "reverse-ok" ) {
      $('.topic').toggleClass("reverse-ok", true );
      localStorage.toggled = "reverse-ok";
   } else {
      $('.topic').toggleClass("reverse-ok", false );
      localStorage.toggled = "";
   }
 
});
</script>