What tags can be used inside the title element?

No tags can be used inside the title element; it only contains text.

The title element is designed to hold plain text that represents the document's title. Any HTML tags placed inside the title element will be ignored by the browser, as the element is meant to provide a simple, text-based title for the document. This ensures that the title is displayed consistently across different browsers and platforms.

<title>My Page Title</title>