<p><strong>This help note is shown because this note of type Render HTML doesn't have required relation to function properly.</strong></p>
<p>Render HTML note type is used for <a href="https://github.com/zadam/trilium/wiki/Scripts">scripting</a>. In short, you have a HTML code note (optionally with some JavaScript) and this note will render it. To make it work, you need to define a relation (in <a class="show-attributes-button">Attributes dialog</a>) called "renderNote" pointing to the HTML note to render. Once that's defined you can click on the "play" button to render.</p>