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The “charset” attribute on the “script” element is obsolete.
A <script> element has been found that is using the now obsolete charset attribute. You can safely remove this attribute.
For example, this is using both type and charset attributes, with their default values. Both can be removed:
<script src="app.js" type="text/javascript" charset="UTF-8"></script>and just use this:
<script src="app.js"></script>Learn more:
Related W3C validator issues
The <meta charset> is expected to appear at the beginning of the document, within the first 1024 bytes. Move it to the beginning of the <head> section, as in this example:
<head>
<meta charset="utf-8">
...
</head>
A character encoding declaration is a mechanism by which the character encoding used to store or transmit a document is specified. For HTML documents, the standard way to declare a document character encoding is by including a <meta> tag with a charset attribute, typically <meta charset="utf-8">.
According to the W3C standard:
The element containing the character encoding declaration must be serialized completely within the first 1024 bytes of the document.
Source:
In order to define the charset encoding of an HTML document, both of these options are valid, but only one of them must appear in the document:
<!-- This is the preferred way -->
<meta charset="UTF-8">
<!-- This is the older way, also valid -->
<meta http-equiv="content-type" content="text/html; charset=UTF-8">Read about specifying the character encoding
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>Learn more:
A <meta> tag has been found that is either malformed, or in a bad place within the document. Check its attributes and context.
For example, the following HTML contains a valid <meta> tag that is raising an issue because of bad context, caused by an <img> tag that shouldn’t be there:
<!DOCTYPE html>
<html lang="">
<head>
<title>Test</title>
<img src="photo.jpg" alt="A smiling cat" />
<meta charset="utf-8" />
</head>
<body>
<p>Some content</p>
</body>
</html>
If we fix that document and move the <img> tag within the body, the issue raised about <meta> disappears because it’s now in a valid context:
<!DOCTYPE html>
<html lang="">
<head>
<title>Test</title>
<meta charset="utf-8" />
</head>
<body>
<p>Some content</p>
<img src="photo.jpg" alt="A smiling cat" />
</body>
</html>Learn more:
A <meta> tag has been found in the document stating that the charset is windows-1251, but it actually is utf-8. You should update the tag to reflect the actual encoding of the document, for example:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
A <meta> tag has been found in the document stating that the charset is windows-1252, but it actually is utf-8. You should update the tag to reflect the actual encoding of the document, for example:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
The 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 type="module">
/* JavaScript module code here */
</script>Learn more:
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.
Learn more:
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>Learn more:
In HTML5 you’re encouraged to use Unicode (UTF-8) character encoding rather than a legacy character encoding such as Latin1 (Windows-1252 or ISO 8859-1).
In short, it can be just a matter of using <meta charset="utf-8"/> in your document, but you should also ensure that your pages are also saved and served as UTF-8.
Rocket Validator checks HTML on your sites using the latest version of W3C Validator Nu HTML Checker, which is intended for HTML5 documents.
The page scanned is using an obsolete doctype, instead of the expected <!DOCTYPE html>.
Learn more:
The old <acronym> element in previous versions is now obsolete, in HTML5 you must use <abbr> instead.
Learn more:
The <font> element, used to define the font face, size and color in previous versions of HTML, is no longer valid in HTML5. Instead, you should rely on CSS styles.
For example, you can define a font size of 12px, bold text with inline styles like this:
<p style="font-size: 12px; font-weight: bold;">some text</p>Learn more about CSS fonts:
The <script> tag allows authors to include dynamic scripts and data blocks in their documents. This tag accepts two optional attributes, type (which is unnecessary if it’s JavaScript, as that’s the default), and src to indicate the URL of the external script to use.
The language attribute is now obsolete and should not be used.
Read more about:
The <meta> element no longer accepts a scheme attribute, it’s now obsolete and should be removed.
For example, old documents adhering to old definitions in DCMI (Dublin Core Metadata Initiative) use this HTML tag to define a date:
<meta name="DC.Date.Created" scheme="W3CDTF" content="2009-11-30" />
As the scheme attribute is now obsolete, it should now be removed. The following HTML code will pass current validations, but you should check the exact definition to use if you want to keep using the DCMI tags.
<meta name="DC.Date.Created" content="2009-11-30" />Learn more:
The default type for <script> tags is JavaScript, so you don’t need to include the type for JS resources.
In HTML5, there’s no need to specify the version attribute - it is now obsolete. Here’s an example minimal HTML document to start with:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Test</title>
</head>
<body>
<p></p>
</body>
</html>Learn more:
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