Rocket Validator automatically checks your pages on the W3C Validator.
HTML issues tagged as alt.
<img> tags, used to include images on a document, require an
alt attribute to describe the contents of the image. This is essential for users that cannot see the image (like screen reader users), or as an alternate text when the image cannot be displayed. Example:
<img src="photo.jpg" alt="Person holding a cat" />
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