Loading icon on async component

Is there a way to show a spinner/loader icon when an hst:component has the property async: true and isn’t fully loaded yet? How would you handle such use case?

Default behaviour is that a page containing such component would render and the component appears later. There isn’t any feedback to the user that extra data is on its way. I can’t find anything in the docs except for https://www.onehippo.org/library/concepts/component-development/asynchronous-hst-components-and-containers.html.

There is a part about customizing scripts. You could trigger showing of your spinner there (before calling load() method). You can hide it in callback method, also described in there.