Opening a background window using the Firefox Add-ons SDK

Question

I am writing a Firefox add-on, and I am using the high-level Firefox Add-on SDK API.

My add-on opens a new window, and opens several tabs in that window.

How can I get this new window to open in the background? I do not want its opening to disrupt the user's focus on the active window.

When opening a tab, there is an inBackground option that can be used for this.

I have searched the windows module documentation high and low, but I cannot find a similar option for when creating new windows!

How do I open this new window in the background?

If Mozilla forbids me from doing so, is there a way I can very quickly push the new window to the background just after it opens, so that it is minimally disruptive?

Answer 1

Not disallowed. Perfectly fine. Do it with a features option of alwaysLowered I think.

Full list of features found here: https://developer.mozilla.org/en-US/docs/Web/API/window.open#Position_and_size_features

var sa = Cc["@mozilla.org/supports-array;1"].createInstance(Ci.nsISupportsArray);
var wuri = Cc["@mozilla.org/supports-string;1"].createInstance(Ci.nsISupportsString);
wuri.data = 'about:blank';
sa.AppendElement(wuri);
let features = "chrome,dialog=no,alwaysLowered";
var wantTabs = false;
if (wantTabs) {
  features += ',all';
}
/*var sDOMWin = aTab.ownerGlobal; //source DOMWindow*/
if (PrivateBrowsingUtils.permanentPrivateBrowsing/* || PrivateBrowsingUtils.isWindowPrivate(sDOMWin)*/) {
   features += ",private";
} else {
   features += ",non-private";
}
var XULWindow = Services.ww.openWindow(null, 'chrome://browser/content/browser.xul', null, features, sa);

You can tag this code onto the end to do something after the XULWindow loads:

XULWindow.addEventListener('load', function() {
  //can lower or raise the window z-index here
  var DOMWindow = XULWindow.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowInternal || Ci.nsIDOMWindow);
  DOMWindow.gBrowser.selectedTab.linkedBrowser.webNavigation.stop(Ci.nsIWebNavigation.STOP_ALL);
}, false);