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HTML Guide

Free site validation

Find out what web pages on your sites are affected by HTML issues.

Document uses the Unicode Private Use Area(s), which should not be used in publicly exchanged documents.

This is a warning that a special character in the Unicode Private Use Area is being used at the document, which might cause it to not work the way you might expect in different browsers/environments.

If you’ve checked the document in different browsers and it’s working fine, you can safely ignore this warning.

What are private-use characters in Unicode?

Private-use characters are code points whose interpretation is not specified by a character encoding standard and whose use and interpretation may be determined by private agreement among cooperating users. Private-use characters are sometimes also referred to as user-defined characters (UDC) or vendor-defined characters (VDC).

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