HTML Checking for Large Sites
Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
A <script> start tag has been found in an unexpected place in the document structure. Check that the <script> section appears within the <head> or <body> sections.
Here’s an example of a script inserted in the head of the document:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<script>
console.log("Hello from the head");
</script>
</head>
<body>
<p></p>
</body>
</html>Learn more:
Related W3C validator issues
A <head> start tag has been found in an unexpected place in the document structure. Check that the <head> section appears before the <body> section, and that is not duplicated.
The <head> section of an HTML document is the container of metadata about the document, and must appear before the <body> section. A common cause of this issue is duplicated <head> sections.
Here is an example of a minimal HTML document structure:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<p></p>
</body>
</html>A stray start tag <html> has been found in the document. As this tag defines the start of the whole HTML document, it should appear only once.
A <style> start tag has been found in an unexpected place in the document structure. Check that the <style> section appears within the <head> section.
Although in general it’s better to put your styles in external stylesheets and apply them using <link> elements, CSS styles can also be included inside a document using the <style> tag. In this case, it should be placed within the <head> section, like in this example:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<style>
p {
color: #26b72b;
}
</style>
</head>
<body>
<p>This text will be green.</p>
</body>
</html>The <script> tag allows authors to include dynamic scripts and data blocks in their documents. When the src is present, this tag accepts a type attribute which must be either:
- an empty string
- text/javascript (that’s the default, so it can be omitted)
- module
Examples:
<!-- This is valid, without a type it defaults to JavaScript -->
<script src="app.js"></script>
<!-- This is valid, but will warn that it can be omitted -->
<script type="text/javascript" src="app.js"></script>
<!-- An empty attribute is valid, but will warn that it can be omitted -->
<script type="" src="app.js"></script>
<!-- The module keyword is also valid as a type -->
<script type="module" src="app.js"></script>
<!-- Any other type is invalid -->
<script type="wrong" src="app.js"></script>
<script type="text/html" src="app.js"></script>
<script type="image/jpeg" src="app.js"></script>Still checking your large sites one page at a time?
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.
The value rocketlazyloadscript used in a <script> tag is not a valid one according to the HTML specification. It is introduced by the WP Rocket Wordpress extension.
The async attribute is boolean: the presence of a boolean attribute on an element represents the true value, and the absence of the attribute represents the false value. As a boolean attribute, it does not need to be passed any value such as true or 1 to activate the async property.
For classic scripts, if the async attribute is present, then the classic script will be fetched in parallel to parsing and evaluated as soon as it is available.
For module scripts, if the async attribute is present then the scripts and all their dependencies will be executed in the defer queue, therefore they will get fetched in parallel to parsing and evaluated as soon as they are available.
<script async src="app.js"></script>
<script async type="module">
/* JavaScript module code here */
</script>25,000 HTML checks per month. Fully automated.
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.
The specified type for an script element is not a valid MIME type as it’s missing a subtype.
A MIME type most-commonly consists of just two parts: a type and a subtype, separated by a slash (/) — with no whitespace between, for example:
text/javascriptThe async and defer boolean attributes of the <script> element control how an external script should be executed once it has been downloaded. The async attribute makes sense when an external script (defined with the src attribute) is loaded, or when defining a script of type module:
<script async src="app.js"></script>
<script async type="module">
/* JavaScript module code here */
</script>The charset attribute on a <script> element can be used to specify the character encoding of an external script, whose URL should be specified on the src attribute.
If the script is not external, then the charset attribute should not be used, as the character encoding of the HTML document will be used.
The defer and async boolean attributes of the <script> element control how an external script should be executed once it has been downloaded. These attributes only make sense when referring to external scripts, so a src attribute must also be present to specify the location of the script.
Example:
<script defer src="app.js"></script>If your script is not external, and is inlined within the HTML document, then you should remove the defer attribute, like in this example:
<script>
console.log("hello");
</script>12,500 Accessibility and HTML checks per week. Fully automated.
Let our automated scanner check your large sites using Axe Core and W3C Validator.