Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
The HTML <shadow> element—an obsolete part of the Web Components technology suite—was intended to be used as a shadow DOM insertion point. You might have used it if you have created multiple shadow roots under a shadow host. It is not useful in ordinary HTML.
| Content categories | Transparent content. |
|---|---|
| Permitted content | Flow content. |
| Tag omission | None, both the starting and ending tag are mandatory. |
| Permitted parents | Any element that accepts flow content. |
| Permitted ARIA roles | None |
| DOM interface | HTMLShadowElement |
Attributes
This element includes the global attributes.
Example
Here is a simple example of using the <shadow> element. It is an HTML file with everything needed in it.
Note: This is an experimental technology. For this code to work, the browser you display it in must support Web Components. See Enabling Web Components in Firefox.
<html>
<head></head>
<body>
<!-- This <div> will hold the shadow roots. -->
<div>
<!-- This heading will not be displayed -->
<h4>My Original Heading</h4>
</div>
<script>
// Get the <div> above with its content
var origContent = document.querySelector('div');
// Create the first shadow root
var shadowroot1 = origContent.createShadowRoot();
// Create the second shadow root
var shadowroot2 = origContent.createShadowRoot();
// Insert something into the older shadow root
shadowroot1.innerHTML =
'<p>Older shadow root inserted by
<shadow></p>';
// Insert into younger shadow root, including <shadow>.
// The previous markup will not be displayed unless
// <shadow> is used below.
shadowroot2.innerHTML =
'<shadow></shadow> <p>Younger shadow
root, displayed because it is the youngest.</p>';
</script>
</body>
</html>
If you display this in a web browser it should look like the following.
Specifications
This element is no longer defined by any specifications.
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 35 | 28 (28)[1] | No support | 26 | No support |
| Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | 37 | 28.0 (28)[1] | No support | ? | ? |
[1] If Shadow DOM is not enabled in Firefox, <shadow> elements will behave like HTMLUnknownElement. Shadow DOM was first implemented in Firefox 33 and is behind a preference, dom.webcomponents.enabled, which is disabled by default.