JSFiddle - React, Tailwind, and code Playground

JavaScript

class FrameCreator{

		constructor(){
    	this.createFrame();
    }
		createFrame(){
    	var iframe = document.createElement('iframe');
      this.iframe = iframe;
      var frameLoaded=this.frameLoaded;
      iframe.onload = function () {
					frameLoaded();
      };
      document.body.appendChild(iframe);
    }
    frameLoaded(){
    		console.log("frame loaded");
    }
}

class CustomFrameCreator extends FrameCreator{
		addContent(){
    		console.log("add content to frame");
    }
    frameLoaded(){
    		console.log();
    }
}


var frame=new CustomFrameCreator();