Navigator: unregisterProtocolHandler() method

Secure context

The Navigator method unregisterProtocolHandler() removes a protocol handler for a given URL scheme.

This method is the inverse of registerProtocolHandler().

Syntax

unregisterProtocolHandler(scheme, url)

Parameters

• scheme
  • : A string containing the permitted scheme in the protocol handler that will be unregistered. For example, you can unregister the handler for SMS text message links by passing the "sms" scheme.
• url
  • : A string containing the URL of the handler. This URL should match the one that was used to register the handler (e.g., it must include %s).

Return value

None (undefined).

Exceptions

• SecurityError DOMException
  • : The user agent blocked unregistration. This might happen if:
    • The scheme (protocol) is invalid, such as a scheme the browser handles itself (https:, about:, etc.)
    • The handler URL’s origin does not match the origin of the page calling this API.
    • The browser requires that this function is called from a secure context.
    • The browser requires that the handler’s URL be over HTTPS.
• SyntaxError DOMException
  • : The %s placeholder is missing from the handler URL.

Permitted schemes

For security reasons, unregisterProtocolHandler() restricts which schemes can be unregistered.

A custom scheme may be unregistered as long as:

• The custom scheme’s name begins with web+
• The custom scheme’s name includes at least 1 letter after the web+ prefix
• The custom scheme has only lowercase ASCII letters in its name.

For example, web+burger, as shown in the Example below.

Otherwise, the scheme must be one of the following:

• bitcoin
• ftp
• ftps
• geo
• im
• irc
• ircs
• magnet
• mailto
• matrix
• mms
• news
• nntp
• openpgp4fpr
• sftp
• sip
• sms
• smsto
• ssh
• tel
• urn
• webcal
• wtai
• xmpp

Examples

If your site is burgers.example.com, and you have a web+burger: scheme, you can unregister the handler for it like so:

navigator.unregisterProtocolHandler(
  "web+burger",
  "https://burgers.example.com/?burger=%s",
);

This script must be run from the same origin as the handler URL (so any page at https://burgers.example.com), and the handler URL must be http or https.

Specifications

Browser compatibility