HTML Checking for Large Sites

Rocket Validator automatically checks your pages on the W3C Validator.

Bad value “tel: X” for attribute “href” on element “a”: Illegal character in scheme data: space is not allowed.

The href attribute on an <a> link contains a space character, which is not allowed. If you’re trying to link to a phone URL, review the href attribute to remove unallowed characters, as in this example:

<!-- Invalid as it contains a space character -->
<a href="tel: +123456789">call me</a>

<!-- Valid -->
<a href="tel:+123456789">call me</a>

Source:

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