rem: prefBranch.addObserver(PREF_SELECTED_WEB, this, true); 
add:  prefBranch.addObserver(PREF_SELECTED_WEB, this, false); window.addEventListener("unload", this, false); 
context:   init: function () {    var _delayedPaneLoad = function(self) {      self._initFeedReaders();      self.updateSelectedReader();    }    setTimeout(_delayedPaneLoad, 0, this);    // For web readers, we need to call setAutoHandler if the    // preview page should be skipped (i.e. PREF_SELECTED_ACTION="reader")    // To do so, we've to add a pref-observer in order to be notified on    // actual pref-changes (i.e. not on pref changes which may not take    // affect when the prefwindow is closed)    var prefBranch = Cc["@mozilla.org/preferences-service;1"].      getService(Ci.nsIPrefBranch2);    prefBranch.addObserver(PREF_SELECTED_WEB, this, true);  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/3543d90ab7963ea21bd6e3e54d8fcc0259f1e78d/feeds.js/buggy/browser/components/preferences/feeds.js