Handling non-HTML xml tags in preview

This issue came when I was using the Advanced Slides community plugin - it has a feature where you can use tags in the markdown for positioning content.
isn’t a HTML tag, so if I do something like this:

<grid>
- foo
- bar
- baz
</grid>

In editing or reading mode, this will render as:

- foo - bar - baz

Other markdown renderers do this as well, so I’m not saying this is a bug. But my browser will just ignore XML tags which aren’t HTML - this snippet on an HTML page will show me a list just fine:

<grid>
<ul>
  <li>foo</li>
  <li>bar</li>
  <li>baz</li>
</ul>
</grid>

Naturally, when there are more complex content I’m authoring with these custom XMl tags - it just absolutely mangles all of the markdown notation - making it very difficult to read the content of these slides.

So is there an option, or a plugin that can help me sort this? Preferably I would want unrecognized inline XML tags to just render as plain text.

You may want to read this with a solution to render them as plain text:

Great explanation - that makes sense. The problem though, with my particular workflow, is that escaping the markup means Advanced Slides just won’t work.

Can I work around this by developing a plugin of my own that hooks into how Obsidian renders the previews - or is that part off limits to plugin development?