Text rendered in h2 heading title about marked

[UziTech]

You can create an lheading tokenizer that never returns a token.

marked.use({
  tokenizer: {
    lheading() {}
  }
});

[UziTech]

That is called a setext heading in markdown. As you can see by the CommonMark demo that is intended behavior.

If you want to prevent the markdown from parsing as markdown you can wrap it in a code fence.

Here's the calculation:

```
456
+456
------
912
```

[Al-phonsio]

Thank you, and sorry for the issue.
Since other users will probably reach this issue : what is the best option to disable Setext heading in marked.