This feature is obsolete.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.

Allows web sites to register themselves as possible handlers for content of a particular MIME type.

Note: Web sites may only register content handlers for themselves. For security reasons, it's not possible for an extension or web site to register content handlers targeting other sites.


navigator.registerContentHandler(mimeType, uri, title);
  • mimeType is the desired MIME type as a string.
  • uri is the URI to the handler as a string.
  • title is the title of the handler presented to the user as a string.


    "My Feed Reader"


For Firefox 2 and above, only the application/vnd.mozilla.maybe.feed, application/atom+xml, and application/rss+xml MIME types are supported. All values have the same effect, and the registered handler will receive feeds in all Atom and RSS versions (see bug 391286).

Firefox is the only browser that implemented this feature, and it wasn't implemented to match the standard. This feature has since been removed from the HTML standard and shouldn't be used.


Specification Status Comment
HTML 5.2
The definition of 'registerContentHandler()' in that specification.
Recommendation This feature is present in HTML 5.2, but has since been removed from the WHATWG HTML Living Standard.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support ? ?2 — 62 ? ? ?
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support ? ? ? ? ? ? ?

See also