It looks like the page-preview is done by an official plugin. I’ll have to do some research to see if I can have it recognize my view too, but my gut feeling is that I won’t be able to if it doesn’t work already. I’ll check with the Obsidian devs.
@Oliver, that sounds like an interesting plugin idea, however I think posting that in the plugin ideas forum would be a good idea. I’ve got my hands pretty full with Slated right now, so I’m currently not looking for new plugin ideas.