I agree some of the WYSIWYG markdown editors are the closest thing to what I want. I quite like Obsidian's editor for what it is, which does a pretty good job b

I agree some of the WYSIWYG markdown editors are the closest thing to what I want. I quite like Obsidian's editor for what it is, which does a pretty good job balancing rendering and letting you edit the actual markdown syntax. But you're editing markdown, not HTML. And, for example, markdown doesn't have definition lists.