This API is available on Firefox OS for internal applications only.


The id property represents the unique id of the thread. Each message belonging to that thread has a property named threadId filled with that same value.


var id =;


A number.


This is a non-standard implementation, but it is discussed at W3C as part of the System Application Working Group.

Specification Status Comment
Messaging API Editor's Draft Editor Draft (WIP).

Browser compatibility

For obvious reasons, support is primarily expected on mobile browsers.

Supported in Firefox OS 1.0.1.

See also

Document Tags and Contributors

Last updated by: mdnwebdocs-bot,