HTML Checking for Large Sites
Rocket Validator automatically checks your pages on the W3C Validator.
HTML issues tagged as preload.
A <link>
element that is using the preload
value in the rel
attribute is missing the as
attribute, used to indicate the type of the resource.
The preload
value of the <link>
element’s rel
attribute lets you declare fetch requests in the HTML’s <head>
, specifying resources that your page will need very soon, which you want to start loading early in the page lifecycle, before browsers’ main rendering machinery kicks in. This ensures they are available earlier and are less likely to block the page’s render, improving performance.
The as
attribute specifies the type of content being loaded by the <link>
, which is necessary for request matching, application of correct content security policy, and setting of correct Accept
request header.
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