Problem with invalid code in the header template part

Hi!

This is not a support request but to inform you that there is a bug in header.html.
At the top of the file it says:

<p><a class="screen-reader-text skip-link" href="#about">Skip to content</a></p>

This code shows up as plain text in the Site Editor. This is not valid block markup and also not the correct way to add a skip link to block themes.

In block themes, the skip link is added automatically for templates that use the <main> element. And it is essential for basic website accessibility that every template has one main element.