rem: return true; 
add: return false; 
context: function MailCheckBeforeOfflineChange(){  var ioService = Components.classes["@mozilla.org/network/io-service;1"]                            .getService(Components.interfaces.nsIIOService);  var goingOnline = ioService.offline;  var bundle = srGetStrBundle("chrome://communicator/locale/utilityOverlay.properties");//  messenger.SetWindow(window, msgWindow);  InitServices();  var prefSendUnsentMessages = gMailOfflinePrefs.getIntPref("offline.send.unsent_messages");  var prefDownloadMessages   = gMailOfflinePrefs.getIntPref("offline.download.download_messages");  if(goingOnline) {    switch(prefSendUnsentMessages) {     case 0:      if(CheckForUnsentMessages()) {         if(! PromptSendMessages())           return false;      }      else         gOfflineManager.goOnline(false /* sendUnsentMessages */,                                  true /* playbackOfflineImapOperations */,                                  msgWindow);      break;    case 1:      gOfflineManager.goOnline(CheckForUnsentMessages() /* sendUnsentMessages */,                                true  /* playbackOfflineImapOperations */,                                msgWindow);      break;    case 2:      gOfflineManager.goOnline(false /* sendUnsentMessages */,                                true /* playbackOfflineImapOperations */,                                msgWindow);      break;    }  }  else {    // going offline    switch(prefDownloadMessages) {	      case 0:        if(! PromptDownloadMessages()) return false;      break;      case 1:        // download news, download mail, send unsent messages, go offline when done, msg window        gOfflineManager.synchronizeForOffline(true, true, false, true, msgWindow);        break;      case 2:        // download news, download mail, send unsent messages, go offline when done, msg window        gOfflineManager.synchronizeForOffline(false, false, false, true, msgWindow);        break;    }  }  return true;}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/cacdb5d48b29001799f6141f7882e8097ea75d3a/mail-offline.js/buggy/mailnews/base/resources/content/mail-offline.js