HTML Checking for Large Sites
Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as auto.
The width and height attributes on <img> elements expect a digit to specify the dimension in pixels. It should not contain units, letters or percent signs.
You can achieve this using CSS instead, for example:
<!-- Invalid syntax, the height attribute expects only digits -->
<img src="photo.jpg" alt="cat" height="auto" />
<!-- Valid syntax using CSS -->
<img src="photo.jpg" alt="cat" style="height: auto" />
The max-width CSS property sets the maximum width of an element. It prevents the used value of the width property from becoming larger than the value specified by max-width.
This property can express a value in different units like px, em, % or ch, and keyword values, but auto is not an allowed value.
Some examples of valid values for max-width:
/* <length> value */
max-width: 3.5em;
/* <percentage> value */
max-width: 75%;
/* Keyword values */
max-width: none;
max-width: max-content;
max-width: min-content;
max-width: fit-content(20em);
/* Global values */
max-width: inherit;
max-width: initial;
max-width: revert;
max-width: unset;
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