diff -Nru metacity-3.20.3/debian/changelog metacity-3.20.3/debian/changelog
--- metacity-3.20.3/debian/changelog	2016-08-13 18:12:01.000000000 +0000
+++ metacity-3.20.3/debian/changelog	2016-10-04 12:57:03.000000000 +0000
@@ -1,3 +1,10 @@
+metacity (1:3.20.3-1ubuntu2) yakkety; urgency=medium
+
+  * Backport upstream patch to fix stack order handling when windows
+    are unmapped (no_remove_on_unmap.diff, LP: #1614050).
+
+ -- Dmitry Shachnev <mitya57@ubuntu.com>  Tue, 04 Oct 2016 15:57:03 +0300
+
 metacity (1:3.20.3-1ubuntu1) yakkety; urgency=medium
 
   * Merge with Debian unstable, remaining changes:
diff -Nru metacity-3.20.3/debian/patches/no_remove_on_unmap.diff metacity-3.20.3/debian/patches/no_remove_on_unmap.diff
--- metacity-3.20.3/debian/patches/no_remove_on_unmap.diff	1970-01-01 00:00:00.000000000 +0000
+++ metacity-3.20.3/debian/patches/no_remove_on_unmap.diff	2016-10-04 12:57:01.000000000 +0000
@@ -0,0 +1,38 @@
+Description: compositor: do not remove window on UnmapNotify event
+Origin: upstream, https://git.gnome.org/browse/metacity/commit/?id=b21f3aed6fefa433
+Bug: https://bugs.launchpad.net/bugs/1614050
+Last-Update: 2016-10-04
+
+--- a/src/compositor/compositor-xrender.c
++++ b/src/compositor/compositor-xrender.c
+@@ -3242,6 +3242,7 @@
+   MetaCompositorXRender *xrc;
+   MetaFrame *frame;
+   Window xwindow;
++  MetaCompWindow *cw;
+ 
+   xrc = (MetaCompositorXRender *) compositor;
+   frame = meta_window_get_frame (window);
+@@ -3251,7 +3252,21 @@
+   else
+     xwindow = meta_window_get_xwindow (window);
+ 
+-  destroy_win (xrc->display, xwindow, FALSE);
++  cw = find_window_in_display (xrc->display, xwindow);
++  if (cw == NULL)
++    return;
++
++  cw->attrs.map_state = IsUnmapped;
++  cw->damaged = FALSE;
++
++  if (cw->extents != None)
++    {
++      dump_xserver_region ("destroy_win", xrc->display, cw->extents);
++      add_damage (cw->screen, cw->extents);
++      cw->extents = None;
++    }
++
++  free_win (cw, FALSE);
+ }
+ 
+ static void
diff -Nru metacity-3.20.3/debian/patches/series metacity-3.20.3/debian/patches/series
--- metacity-3.20.3/debian/patches/series	1970-01-01 00:00:00.000000000 +0000
+++ metacity-3.20.3/debian/patches/series	2016-10-04 12:54:38.000000000 +0000
@@ -0,0 +1 @@
+no_remove_on_unmap.diff