External links without noopener/noreferrer are a potential security risk.

examples/webgl_postprocessing_sobel.html

@@ -45,7 +45,7 @@
 		<script src="js/postprocessing/ShaderPass.js"></script>
 
 		<div id="info">
-			<a href="https://threejs.org" target="_blank">three.js</a> - webgl - postprocessing - sobel (edge detection)
+			<a href="https://threejs.org" target="_blank" rel="noopener noreferrer">three.js</a> - webgl - postprocessing - sobel (edge detection)
 		</div>
 
 		<script>