Huh, I guess you can’t have a user confirm a form submission without JavaScript. At least not that I could find. Darn. 🤔

@heyloura If you're okay with not having a dialog box, maybe something like this?

<form action="/delete-something">
<label>
<input type="checkbox" required> I'm super-duper sure I want to do this.
</label>
<button>Delete</button>
</form>

@heyloura Or, like this, if you style the summary element to look like a button and the form element to look like a dialog box.

<details>
<summary>Delete</summary>
<form action="/delete-something">
Are you sure?
<button>Yes, delete something</button>
</form>
</details>