one or more <a href="RenderKit.html" title="class in jakarta.faces.render"><code>RenderKit</code></a> instances at web
 application startup. They are made available through calls to the <code>getRenderKit()</code> methods of
 <a href="RenderKitFactory.html" title="class in jakarta.faces.render"><code>RenderKitFactory</code></a>. Because <a href="RenderKit.html" title="class in jakarta.faces.render"><code>RenderKit</code></a> instances are shared, they must be implemented in a thread-safe
 manner. Due to lim