Html 如何在tinymce 5编辑器之后创建外部div

我已经尝试了两天，在tinymce编辑器之后从tinymce init内部创建一个外部div。我想创建nextElementSibling，以便文本直接显示在tinymce编辑器框的下方/后面。我有很多文档，尝试了很多东西，现在是时候寻求帮助了

下面是在tinymce之外工作的普通js

   var id = getElementById('aboutme'); //this is the html textarea
   var dv = id.parentNode.insertBefore(document.createElement("div"), id.nextSibling);
   dv.id = "aboutme_countdown";
   dv.textContent = "All Characters Remaining";
   dv.style = "display: block";
        

我需要将js代码转换为tinymce代码，但我没有任何运气

setup: function(ed)
{
        var limit = 25;
        var pelem = $(ed.getContainer()).find('#aboutme');  //both id and name of html textarea 

        /* in case the countdown div has not been created we */
        /* capture the error and create the element */
        
        try{
           
             var aboutme = pelem.prevObject[0].nextElementSibling || pelem.prevObject[0].nextSibling; //this works
         
           } catch (error) {
               
                         /* create the new countdown div */
                         /* this creates the div after the tinyMCE editor as a separate div */
                
                         /* this is the part i cannot get to work after trying many many differt ways and syntax. It tells me the dom does not exist */

                         var dv = tinymce.activeEditor.dom.create('div', {id: 'aboutme_countdown', style: 'display:block'}, 'All Characters Remaining');
                         tinymce.activeEditor.selection.setNode(dv);                 
        

                        }//close try catch

  }, //close setup

我已经读了很多tinymce文档，直到我准备好尖叫lol。。。帮忙，谢谢

那么这里的正确语法是什么？错误是dom为空

 var dv = tinymce.activeEditor.dom.create('div', {id: 'aboutme_countdown', style: 'display:block'}, 'All Characters Remaining'); 
 tinymce.activeEditor.selection.setNode(dv);