diff -Nru gtk+3.0-3.18.9/debian/changelog gtk+3.0-3.18.9/debian/changelog
--- gtk+3.0-3.18.9/debian/changelog	2016-06-29 17:28:16.000000000 +0200
+++ gtk+3.0-3.18.9/debian/changelog	2017-01-23 14:08:54.000000000 +0100
@@ -1,3 +1,12 @@
+gtk+3.0 (3.18.9-1ubuntu3.2) xenial; urgency=medium
+
+  * d/p/gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch:
+    add proposed patch from upstream Bugzilla to let GDK X11
+    initialization complete successfully when libGL.so.1 is not
+    available (Closes: #847366, LP: #1550983)
+
+ -- Dariusz Gadomski <dariusz.gadomski@canonical.com>  Mon, 23 Jan 2017 14:08:54 +0100
+
 gtk+3.0 (3.18.9-1ubuntu3.1) xenial; urgency=medium
 
   * debian/patches/unity-border-radius.patch:
diff -Nru gtk+3.0-3.18.9/debian/patches/gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch gtk+3.0-3.18.9/debian/patches/gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch
--- gtk+3.0-3.18.9/debian/patches/gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch	1970-01-01 01:00:00.000000000 +0100
+++ gtk+3.0-3.18.9/debian/patches/gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch	2017-01-23 14:08:54.000000000 +0100
@@ -0,0 +1,51 @@
+From 1fb5f0aed9976437d8c9c82071efe9a447d73de1 Mon Sep 17 00:00:00 2001
+From: Emmanuele Bassi <ebassi@gnome.org>
+Date: Fri, 20 Jan 2017 18:07:01 +0000
+Subject: [PATCH] gdk/x11: Check if we have access to GL before using GLX API
+
+If the platform does not have access to libGL then any call to GL and
+GLX API through libepoxy will fail with an assertion. Until such time
+that libepoxy exposes API for us to use, we can simply dlopen libGL
+ourselves and do a symbol check.
+
+[smcv: fix typo]
+
+Bug: https://bugzilla.gnome.org/show_bug.cgi?id=775279
+Bug-Debian: https://bugs.debian.org/847366
+Bug-Ubuntu: https://bugs.launchpad.net/bugs/1550983
+
+--- gtk+3.0-3.18.9.orig/gdk/x11/gdkglcontext-x11.c
++++ gtk+3.0-3.18.9/gdk/x11/gdkglcontext-x11.c
+@@ -762,6 +762,32 @@ gdk_x11_screen_init_gl (GdkScreen *scree
+   if (_gdk_gl_flags & GDK_GL_DISABLE)
+     return FALSE;
+ 
++  /* This is an ad hoc check that bypasses libepoxy to check if libGL.so is
++   * unavailable, and disables GL support if that's the case
++   *
++   * Ideally, libepoxy should do this for us, but that would require adding
++   * new API, and we'd need a fallback anyway.
++   */
++  {
++    Bool (* fp_glXQueryExtension) (Display *dpy, int *err_base, int *ev_base);
++    GModule *module = g_module_open ("libGL.so.1", 0);
++
++    if (module == NULL)
++      {
++        GDK_NOTE (OPENGL, g_message ("No libGL.so found"));
++        return FALSE;
++      }
++
++    if (!g_module_symbol (module, "glXQueryExtension", (gpointer *) &fp_glXQueryExtension))
++      {
++        GDK_NOTE (OPENGL, g_message ("No glXQueryExtension symbol found"));
++        g_module_close (module);
++        return FALSE;
++      }
++
++    g_module_close (module);
++  }
++
+   dpy = gdk_x11_display_get_xdisplay (display);
+ 
+   if (!glXQueryExtension (dpy, &error_base, &event_base))
diff -Nru gtk+3.0-3.18.9/debian/patches/series gtk+3.0-3.18.9/debian/patches/series
--- gtk+3.0-3.18.9/debian/patches/series	2016-06-29 17:23:14.000000000 +0200
+++ gtk+3.0-3.18.9/debian/patches/series	2017-01-23 14:08:54.000000000 +0100
@@ -26,3 +26,4 @@
 ubuntu_fileselector_behaviour.patch
 unity-border-radius.patch
 unity-headerbar-maximized-mode.patch
+gdk-x11-Check-if-we-have-access-to-GL-before-using-G.patch