title: Why was HTML5 Web Workers support removed from the Android browser in versions 2.2 and up?
body: <p>I'm trying to learn something about JavaScript threading. And from a tutorial I learned about HTML5 API web worker. This API enables JavaScript multi-threading. So I start to figure out how and where can I use this feature.</p>
  <p>Form <a href="http://caniuse.com/#search=worker" rel="nofollow noreferrer">http://caniuse.com/#search=worker</a></p>
  <p>I find this API is only supported in <em>lower</em> version of Android browser. It is unavailable in Android 2.2 and later.</p>
  <p>Is this result correct? If it is, is it because of the performance consideration?</p>
  <p>On which version will this API be available?</p>