old_contents: 
  ( function () {
  
  
  	/* Remove start screen ( or press some button ) */
  
  	let button = document.getElementById( 'startButton' );
  	if ( button ) {
  
  		button.click();
  
  	}
  
  
  	/* Remove dat.gui and fonts */
  
  	let style = document.createElement( 'style' );
  	style.type = 'text/css';
  	style.innerHTML = `body { font size: 0 !important; }
        #info, button, input, body > div.dg.ac, body > div.lbl { display: none !important; }`;
  	let head = document.getElementsByTagName( 'head' );
  	if ( head.length > 0 ) {
  
  		head[ 0 ].appendChild( style );
  
  	}
  
  
  	/* Remove stats.js */
  
  	let canvas = document.getElementsByTagName( 'canvas' );
  	for ( let i = 0; i < canvas.length; ++ i ) {
  
  		if ( canvas[ i ].height === 48 ) {
  
  			canvas[ i ].style.display = 'none';
  
  		}
  
  	}
  
  }() );
  
new_contents: 
  ( function () {
  
  
  	/* Remove start screen ( or press some button ) */
  
  	const button = document.getElementById( 'startButton' );
  
  	if ( button ) {
  
  		button.click();
  
  	}
  
  
  	/* Remove dat.gui and fonts */
  
  	const style = document.createElement( 'style' );
  	style.type = 'text/css';
  	style.innerHTML = `body { font size: 0 !important; }
        #info, button, input, body > div.dg.ac, body > div.lbl { display: none !important; }`;
  
  	const head = document.getElementsByTagName( 'head' );
  
  	if ( head.length > 0 ) {
  
  		head[ 0 ].appendChild( style );
  
  	}
  
  	/* Remove stats.js */
  
  	const canvas = document.getElementsByTagName( 'canvas' );
  
  	for ( let i = 0; i < canvas.length; ++ i ) {
  
  		if ( canvas[ i ].height === 48 ) {
  
  			canvas[ i ].style.display = 'none';
  
  		}
  
  	}
  
  }() );
  
subject: Clean up.