Get Firefox Window ID (WId) under X11

Question

I am trying to figure out how to get the Firefox X11 WId (window id) from the Firefox add-on / extension.

Checked nsIWindowMediator, nsIXULBrowserWindow, nsIXULWindowbut not found.

I would prefer not to use the usual (ab) method with Xlib to search in the window tree that matches the attributes of the current window, such as type, type, etc.

Answer 1

I think the only place you can get it is nsIEmbeddingSiteWindow.siteWindow (its type is GtkWidget*on Linux, it should be possible to get the window id from this). Getting an instance nsIEmbeddingSiteWindowfor a top-level window is relatively simple:

Components.utils.import("resource://gre/modules/Services.jsm");

var embedding = Services.ww.getChromeForWindow(window)
                  .QueryInterface(Components.interfaces.nsIEmbeddingSiteWindow);

The problem is that the property is siteWindowmarked with an annotator [noscript]- it is not accessible from JavaScript. So I had to use the XPCOM binary component (written in C ++) in order to actually get this property. I don't know if this is right for you. The only alternative is to search the window tree.