220429 - [Gtk2] leak GDK windows from references in GdkDisplayX11::translate_queue

Status: RESOLVED WORKSFORME

(Core :: Widget: Gtk, defect)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

In the Gtk2 port we leak a lot of GDK windows with leaked references held in the
translate_queue of GdkDisplayX11 objects.  They're put there by the code in
gdk_window_queue in gdk/x11/gdkgeometry-x11.c, called from
_gdk_windowing_window_queue_antiexpose.  I'm not sure why they're not removed --
they should be removed by _gdk_window_process_expose.  (Even if they're not,
gdk_window_queue prevents the queue from having more than 64 antiexpose items,
so they should get removed eventually, but this can probably keep windows around
longer than they need to be, although I'm not sure how much).

I'm wondering if the code we use to wrap the GDK code (such as expose_event_cb,
in nsWindow.cpp) is preventing the normal handling from going through and
causing the translate_queue to be cleaned up.