Non-space character inside “noscript” inside “head”.

A <noscript> inside the <head> contains text, but there it may only hold <link>, <style> and <meta> elements.

The <head> is never rendered, so a <noscript> placed there can only change metadata, for example by loading a fallback stylesheet. Whitespace and comments are fine. Any other character counts, including  , because a non-breaking space isn't whitespace to the HTML parser.

When JavaScript is off, the parser treats that text as the start of the page content. It closes the <noscript> and the <head> early and opens the <body> there. The text and everything after it end up in the body, which is why the validator usually follows this error with Stray end tag “noscript”, Stray end tag “head” and a complaint about a second <body> start tag. Any <meta> or <link> that comes after the <noscript> also lands in the body.

A message for visitors without JavaScript belongs in a <noscript> inside the <body>. Keep the <noscript> in the <head> for metadata only, or remove it.

Invalid example

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Example</title>
    <noscript>Please enable JavaScript to use this site.</noscript>
  </head>
  <body>
    <p>Hello</p>
  </body>
</html>

Valid example

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Example</title>
    <noscript>
      <link rel="stylesheet" href="no-js.css">
    </noscript>
  </head>
  <body>
    <noscript>
      <p>Please enable JavaScript to use this site.</p>
    </noscript>
    <p>Hello</p>
  </body>
</html>

Learn more:

MDN Reference

MDN Web Docs: The noscript element

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MDN Reference

MDN Web Docs: The head element

→

WHATWG Spec

HTML Standard: Scripting

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