Rocket Validator automatically checks your pages on the W3C Validator.
HTML issues tagged as required attribute.
src attribute for
<img> tags is required, to define the source of the image, like in this example:
<img src="photo.jpg" alt="wombat" />
<img> tags used to display images require the attribute
src to indicate the source of the image, for example
<img src="/img/photo.jpg" />.
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Keep your sites healthy checking for A11Y/HTML issues on an automated schedule.