firefox - open websocket connection firefox addon

Question

Is it possible for a firefox addon to establish a websocket connections?

When I try:

var wsUri = "ws://echo.websocket.org/";
var ws = gBrowser.contentWindow.window.WebSocket ||
         gBrowser.contentWindow.window.MozWebSocket;    
var websocket = new ws(wsUri);

In the Error Console the message says

Error: Firefox can't establish a connection to the server at ws://echo.websocket.org/.

Answer 1

目前，似乎唯一的选择是通过PageWorker. 在这个网站上有一个如何做到这一点的例子：

http://austinhartzheim.me/blog/4/websockets-firefox-sdk-addons/