HTML check: X-UA-Compatible HTTP header must have the value “IE=edge”, was “IE=10”.

About This HTML Issue

The X-UA-Compatible meta tag or HTTP header value must be set to IE=edge instead of IE=10 for modern browser compatibility.

The X-UA-Compatible HTTP header or <meta http-equiv="X-UA-Compatible"> element instructs Internet Explorer which document mode to use. Setting it to IE=10 forces the page into IE10 rendering mode, which is outdated and may cause issues with modern web standards. The recommended value is IE=edge, which tells IE to use the highest supported mode available, ensuring the browser uses the latest standards.

Example of the correct <meta> tag for compliance:

<!DOCTYPE html>
<html lang="en">
<head>
  <title>Correct X-UA-Compatible Example</title>
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
</head>
<body>
<!-- Page content -->

</body>
</html>

Remove any instance like IE=10 and replace with IE=edge to resolve the validator issue.

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MDN Reference

MDN: x-ua-compatible

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