On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 1 on 2008-12-11
In Chrome Android version 18 on 2012-06-27
Not in Edge
In Firefox version 48 on 2016-08-02
In Firefox for Android version 48 on 2016-08-02
In Internet Explorer version 5 on 1999-03-18
In Quest Browser version 5.0 on undefined
In Opera version 8 on 2005-04-19
In Opera Android version 10.1 on 2010-11-09
In Safari version 3 on 2007-10-26
In Safari on iOS version 1 on 2007-06-29
In Samsung Internet version 1.0 on 2013-04-27
In WebView Android version 4.4 on 2013-12-09