diff -up firefox-63.0.3/widget/gtk/mozcontainer.cpp.mozbz1507475 firefox-63.0.3/widget/gtk/mozcontainer.cpp
--- firefox-63.0.3/widget/gtk/mozcontainer.cpp.mozbz1507475	2018-11-15 01:20:56.000000000 +0100
+++ firefox-63.0.3/widget/gtk/mozcontainer.cpp	2018-11-26 09:36:13.083772336 +0100
@@ -169,6 +169,8 @@ moz_container_class_init (MozContainerCl
 }
 
 #if defined(MOZ_WAYLAND)
+static struct wl_subcompositor *subcompositor;
+
 static void
 registry_handle_global (void *data,
                         struct wl_registry *registry,
@@ -176,9 +178,8 @@ registry_handle_global (void *data,
                         const char *interface,
                         uint32_t version)
 {
-    MozContainer *container = MOZ_CONTAINER(data);
     if(strcmp(interface, "wl_subcompositor") == 0) {
-        container->subcompositor =
+        subcompositor =
             static_cast<wl_subcompositor*>(wl_registry_bind(registry,
                                            name,
                                            &wl_subcompositor_interface,
@@ -197,6 +198,24 @@ static const struct wl_registry_listener
     registry_handle_global,
     registry_handle_global_remove
 };
+
+struct wl_subcompositor* subcompositor_get(void)
+{
+    if (!subcompositor) {
+        GdkDisplay *gdk_display = gdk_display_get_default();
+        // Available as of GTK 3.8+
+        static auto sGdkWaylandDisplayGetWlDisplay =
+            (wl_display *(*)(GdkDisplay *))
+            dlsym(RTLD_DEFAULT, "gdk_wayland_display_get_wl_display");
+
+        wl_display* display = sGdkWaylandDisplayGetWlDisplay(gdk_display);
+        wl_registry* registry = wl_display_get_registry(display);
+        wl_registry_add_listener(registry, &registry_listener, nullptr);
+        wl_display_dispatch(display);
+        wl_display_roundtrip(display);
+    }
+    return subcompositor;
+}
 #endif
 
 void
@@ -208,25 +227,10 @@ moz_container_init (MozContainer *contai
 
 #if defined(MOZ_WAYLAND)
     {
-      container->subcompositor = nullptr;
       container->surface = nullptr;
       container->subsurface = nullptr;
       container->eglwindow = nullptr;
       container->parent_surface_committed = false;
-
-      GdkDisplay *gdk_display = gtk_widget_get_display(GTK_WIDGET(container));
-      if (GDK_IS_WAYLAND_DISPLAY (gdk_display)) {
-          // Available as of GTK 3.8+
-          static auto sGdkWaylandDisplayGetWlDisplay =
-              (wl_display *(*)(GdkDisplay *))
-              dlsym(RTLD_DEFAULT, "gdk_wayland_display_get_wl_display");
-
-          wl_display* display = sGdkWaylandDisplayGetWlDisplay(gdk_display);
-          wl_registry* registry = wl_display_get_registry(display);
-          wl_registry_add_listener(registry, &registry_listener, container);
-          wl_display_dispatch(display);
-          wl_display_roundtrip(display);
-        }
     }
 #endif
 }
@@ -298,7 +302,7 @@ moz_container_map_surface(MozContainer *
         }
 
         container->subsurface =
-          wl_subcompositor_get_subsurface (container->subcompositor,
+          wl_subcompositor_get_subsurface (subcompositor_get(),
                                            container->surface,
                                            gtk_surface);
         gint x, y;
diff -up firefox-63.0.3/widget/gtk/mozcontainer.h.mozbz1507475 firefox-63.0.3/widget/gtk/mozcontainer.h
--- firefox-63.0.3/widget/gtk/mozcontainer.h.mozbz1507475	2018-11-15 01:20:56.000000000 +0100
+++ firefox-63.0.3/widget/gtk/mozcontainer.h	2018-11-26 09:36:13.083772336 +0100
@@ -69,7 +69,6 @@ struct _MozContainer
     GList         *children;
 
 #ifdef MOZ_WAYLAND
-    struct wl_subcompositor *subcompositor;
     struct wl_surface       *surface;
     struct wl_subsurface    *subsurface;
     struct wl_egl_window    *eglwindow;
diff -up firefox-63.0.3/widget/gtk/nsGtkKeyUtils.cpp.mozbz1507475 firefox-63.0.3/widget/gtk/nsGtkKeyUtils.cpp
--- firefox-63.0.3/widget/gtk/nsGtkKeyUtils.cpp.mozbz1507475	2018-11-15 01:20:56.000000000 +0100
+++ firefox-63.0.3/widget/gtk/nsGtkKeyUtils.cpp	2018-11-26 09:36:13.084772332 +0100
@@ -584,68 +584,37 @@ static const struct wl_keyboard_listener
     keyboard_handle_modifiers,
 };
 
-static void
-seat_handle_capabilities(void *data, struct wl_seat *seat,
-                         unsigned int caps)
-{
-    static wl_keyboard *keyboard = nullptr;
-
-    if (caps & WL_SEAT_CAPABILITY_KEYBOARD) {
-        keyboard = wl_seat_get_keyboard(seat);
-        wl_keyboard_add_listener(keyboard, &keyboard_listener, nullptr);
-    } else if (keyboard && !(caps & WL_SEAT_CAPABILITY_KEYBOARD)) {
-        wl_keyboard_destroy(keyboard);
-        keyboard = nullptr;
-    }
-}
-
-static const struct wl_seat_listener seat_listener = {
-      seat_handle_capabilities,
-};
-
-static void
-gdk_registry_handle_global(void               *data,
-                           struct wl_registry *registry,
-                           uint32_t            id,
-                           const char         *interface,
-                           uint32_t            version)
-{
-    if (strcmp(interface, "wl_seat") == 0) {
-        wl_seat *seat =
-            (wl_seat*)wl_registry_bind(registry, id, &wl_seat_interface, 1);
-        wl_seat_add_listener(seat, &seat_listener, data);
-    }
-}
-
-static void
-gdk_registry_handle_global_remove(void               *data,
-                                 struct wl_registry *registry,
-                                 uint32_t            id)
-{
-}
-
-static const struct wl_registry_listener keyboard_registry_listener = {
-    gdk_registry_handle_global,
-    gdk_registry_handle_global_remove
-};
-
 void
 KeymapWrapper::InitBySystemSettingsWayland()
 {
-    // Available as of GTK 3.8+
-    static auto sGdkWaylandDisplayGetWlDisplay =
-        (wl_display *(*)(GdkDisplay *))
-        dlsym(RTLD_DEFAULT, "gdk_wayland_display_get_wl_display");
-
-    wl_display *display =
-        sGdkWaylandDisplayGetWlDisplay(gdk_display_get_default());
-    wl_registry_add_listener(wl_display_get_registry(display),
-                             &keyboard_registry_listener, this);
-
-    // Call wl_display_roundtrip() twice to make sure all
-    // callbacks are processed.
-    wl_display_roundtrip(display);
-    wl_display_roundtrip(display);
+    GdkDeviceManager* manager =
+        gdk_display_get_device_manager(gdk_display_get_default());
+    GList* devices =
+        gdk_device_manager_list_devices(manager, GDK_DEVICE_TYPE_MASTER);
+    GdkDevice* device = nullptr;
+
+    GList* list = devices;
+    while (devices) {
+        device = static_cast<GdkDevice*>(devices->data);
+        if (gdk_device_get_source(device) == GDK_SOURCE_KEYBOARD) {
+            break;
+        }
+        devices = devices->next;
+   }
+
+   if (list) {
+       g_list_free(list);
+   }
+
+   if (device) {
+      // Present in Gtk+ 3.10
+      static auto sGdkWaylandDeviceGetWlKeyboard =
+          (struct wl_keyboard * (*)(GdkDevice *device))
+          dlsym(RTLD_DEFAULT, "gdk_wayland_device_get_wl_keyboard");
+
+      wl_keyboard_add_listener(sGdkWaylandDeviceGetWlKeyboard(device),
+                               &keyboard_listener, nullptr);
+   }
 }
 #endif