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HTML Guide

Free site validation

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

Bad value X for attribute “srcset” on element “source”: No width specified for image Y. (When the “sizes” attribute is present, all image candidate strings must specify a width.)

The sizes attribute is used to complement the srcset attribute on an <img> tag for responsive images. When this attribute is present, all image candidates must specify its width.

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Related W3C validator issues