On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 9 on 2011-02-03
In Chrome Android version 18 on 2012-06-27
In Edge version 12 on 2015-07-29
In Firefox version 4 on 2011-03-22 Note: In Firefox 56, the implementation has been updated so that the formAction property returns the correct form submission URL, as per spec, when the associated button is being used to submit a form (bug 1366361).
In Firefox for Android version 4 on 2011-03-29 Note: In Firefox for Android 56, the implementation has been updated so that the formAction property returns the correct form submission URL, as per spec, when the associated button is being used to submit a form (bug 1366361).
In Internet Explorer version 10 on 2012-10-26
In Quest Browser version 5.0 on undefined
In Opera version ≤12.1 on undefined
In Opera Android version ≤12.1 on undefined
In Safari version 5.1 on 2011-07-20
In Safari on iOS version 5 on 2011-10-12
In Samsung Internet version 1.0 on 2013-04-27
In WebView Android version 3 on 2011-02-22
In WebView on iOS version 5 on 2011-10-12