1 erreur found
Line 3, Column 1: Missing xmlns attribute for element html. The value should be: http://www.w3.org/1999/xhtml.
<html lang="fr"><head>
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Many Document Types based on XML need a mandatory xmlns="" on the root element. For example, the root element for XHTML will look like:
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">