Rendering something in edit mode

Greetings, Bubble plug-meisters!

I’m new to Bubble and delving into plug-in development.

I have a simple plugin element that displays some text on the page and shows an alert when clicked. This works as expected when running my app.

What I don’t quite grasp is how to display something in edit mode. All that appears is the element outline with handles for resizing. How do I render something in edit mode?

I must be overlooking something obvious.

As best I can tell, all you can do is specify an image placeholder in the element’s general properties. There appears to be no way to render HTML as the placeholder.

If that’s correct, it implies that if I have a custom element which displays some user-specified text, I can’t create a preview of the element in edit mode. Is that right?