For Markdown files, this isn't needed because the Markdown converter takes care of this.

- Add headings to examples section
- Clarify styles and customization options in examples
- Add dismiss buttons to all toasts
- Missing period added for consistency
- Update roles, tweak text

Also remove close button everywhere just let it when autohide is set to false

When the address bar is hidden, sometimes the visual position of the controls is out of sync with its logical position.

Reduces duplication and makes maintenance easier.

Add `tabindex="-1"` and `aria-disabled="true"` to disabled link