core: Setup and use ownership chains

As with other parts, make objects have the ability to walk up the
ownership chain to the context, to get things like the Wayland
compositor or backend instances.

Contains these squashed commits:

display: Don't get backend from singleton

window: Don't get backend from singleton

keybindings: Don't get backend from singleton

workspace: Don't get backend from singleton

display: Don't get Wayland compositor from singleton

selection: Add display getter

context/main: Get backend directly from the context

clipboard-manager: Don't get display from singleton

stack-tracker: Don't use singleton MetaLater API

startup-notification: Hook up sequences and activations to display

This allows using context aware API directly.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2718>

18 files changed, 243 insertions, 97 deletions

diff --git a/src/core/constraints.c b/src/core/constraints.c
index a1140d5f5..86a3effe4 100644
--- a/src/core/constraints.c
+++ b/src/core/constraints.c
@@ -121,6 +121,8 @@ typedef enum
 
 typedef struct
 {
+  MetaBackend *backend;
+
   MetaRectangle        orig;
   MetaRectangle        current;
   MetaRectangle        temporary;
@@ -205,7 +207,8 @@ static gboolean constrain_partially_onscreen (MetaWindow         *window,
                                               ConstraintPriority  priority,
                                               gboolean            check_only);
 
-static void setup_constraint_info        (ConstraintInfo      *info,
+static void setup_constraint_info        (MetaBackend         *backend,
+                                          ConstraintInfo      *info,
                                           MetaWindow          *window,
                                           MetaMoveResizeFlags  flags,
                                           MetaGravity          resize_gravity,
@@ -291,6 +294,9 @@ meta_window_constrain (MetaWindow          *window,
                        int                 *rel_x,
                        int                 *rel_y)
 {
+  MetaDisplay *display = meta_window_get_display (window);
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   ConstraintInfo info;
   ConstraintPriority priority = PRIORITY_MINIMUM;
   gboolean satisfied = FALSE;
@@ -301,7 +307,8 @@ meta_window_constrain (MetaWindow          *window,
               orig->x, orig->y, orig->width, orig->height,
               new->x,  new->y,  new->width,  new->height);
 
-  setup_constraint_info (&info,
+  setup_constraint_info (backend,
+                         &info,
                          window,
                          flags,
                          resize_gravity,
@@ -338,20 +345,21 @@ meta_window_constrain (MetaWindow          *window,
 }
 
 static void
-setup_constraint_info (ConstraintInfo      *info,
+setup_constraint_info (MetaBackend         *backend,
+                       ConstraintInfo      *info,
                        MetaWindow          *window,
                        MetaMoveResizeFlags  flags,
                        MetaGravity          resize_gravity,
                        const MetaRectangle *orig,
                        MetaRectangle       *new)
 {
-  MetaBackend *backend = meta_get_backend ();
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
   MetaWorkspace *cur_workspace;
   MetaPlacementRule *placement_rule;
 
+  info->backend = backend;
   info->orig    = *orig;
   info->current = *new;
   info->temporary = *orig;
@@ -532,9 +540,8 @@ place_window_if_needed(MetaWindow     *window,
       !window->minimized &&
       !window->fullscreen)
     {
-      MetaBackend *backend = meta_get_backend ();
       MetaMonitorManager *monitor_manager =
-        meta_backend_get_monitor_manager (backend);
+        meta_backend_get_monitor_manager (info->backend);
       MetaRectangle orig_rect;
       MetaRectangle placed_rect;
       MetaWorkspace *cur_workspace;
@@ -1688,9 +1695,8 @@ constrain_to_single_monitor (MetaWindow         *window,
                              ConstraintPriority  priority,
                              gboolean            check_only)
 {
-  MetaBackend *backend = meta_get_backend ();
   MetaMonitorManager *monitor_manager =
-    meta_backend_get_monitor_manager (backend);
+    meta_backend_get_monitor_manager (info->backend);
 
   if (priority > PRIORITY_ENTIRELY_VISIBLE_ON_SINGLE_MONITOR)
     return TRUE;
diff --git a/src/core/display.c b/src/core/display.c
index 804936781..c5a353369 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -211,6 +211,24 @@ meta_display_show_osd (MetaDisplay *display,
                        const gchar *icon_name,
                        const gchar *message);
 
+static MetaBackend *
+backend_from_display (MetaDisplay *display)
+{
+  MetaContext *context = meta_display_get_context (display);
+
+  return meta_context_get_backend (context);
+}
+
+#ifdef HAVE_WAYLAND
+static MetaWaylandCompositor *
+wayland_compositor_from_display (MetaDisplay *display)
+{
+  MetaContext *context = meta_display_get_context (display);
+
+  return meta_context_get_wayland_compositor (context);
+}
+#endif
+
 static void
 meta_display_get_property(GObject         *object,
                           guint            prop_id,
@@ -614,7 +632,7 @@ meta_display_remove_pending_pings_for_window (MetaDisplay *display,
 static MetaCompositor *
 create_compositor (MetaDisplay *display)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
 
 #ifdef HAVE_WAYLAND
 #ifdef HAVE_NATIVE_BACKEND
@@ -643,7 +661,7 @@ meta_display_cancel_touch (MetaDisplay *display)
   if (!meta_is_wayland_compositor ())
     return;
 
-  compositor = meta_wayland_compositor_get_default ();
+  compositor = wayland_compositor_from_display (display);
   meta_wayland_touch_cancel (compositor->seat->touch);
 #endif
 }
@@ -667,7 +685,7 @@ gesture_tracker_state_changed (MetaGestureTracker   *tracker,
       {
         MetaBackend *backend;
 
-        backend = meta_get_backend ();
+        backend = backend_from_display (display);
         meta_backend_finish_touch_sequence (backend, sequence, state);
         break;
       }
@@ -795,7 +813,7 @@ meta_display_init_x11 (MetaDisplay         *display,
                        GAsyncReadyCallback  callback,
                        gpointer             user_data)
 {
-  MetaWaylandCompositor *compositor = meta_wayland_compositor_get_default ();
+  MetaWaylandCompositor *compositor = wayland_compositor_from_display (display);
 
   g_autoptr (GTask) task = NULL;
 
@@ -933,7 +951,7 @@ meta_display_new (MetaContext  *context,
   if (meta_is_wayland_compositor ())
     {
       MetaWaylandCompositor *wayland_compositor =
-        meta_wayland_compositor_get_default ();
+        wayland_compositor_from_display (display);
       MetaX11DisplayPolicy x11_display_policy;
 
       meta_wayland_compositor_init_display (wayland_compositor, display);
@@ -1277,7 +1295,7 @@ meta_grab_op_is_moving (MetaGrabOp op)
 gboolean
 meta_display_windows_are_interactable (MetaDisplay *display)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaStage *stage = META_STAGE (meta_backend_get_stage (backend));
 
   if (clutter_stage_get_grab_actor (CLUTTER_STAGE (stage)))
@@ -1427,9 +1445,9 @@ void
 meta_display_sync_wayland_input_focus (MetaDisplay *display)
 {
 #ifdef HAVE_WAYLAND
-  MetaWaylandCompositor *compositor = meta_wayland_compositor_get_default ();
+  MetaWaylandCompositor *compositor = wayland_compositor_from_display (display);
   MetaWindow *focus_window = NULL;
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   ClutterBackend *clutter_backend = meta_backend_get_clutter_backend (backend);
   ClutterSeat *seat = clutter_backend_get_default_seat (clutter_backend);
   MetaStage *stage = META_STAGE (meta_backend_get_stage (backend));
@@ -1739,7 +1757,7 @@ root_cursor_prepare_at (MetaCursorSpriteXcursor *sprite_xcursor,
                         MetaDisplay             *display)
 {
   MetaCursorSprite *cursor_sprite = META_CURSOR_SPRITE (sprite_xcursor);
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
 
   if (meta_backend_is_stage_views_scaled (backend))
     {
@@ -1787,7 +1805,7 @@ meta_display_reload_cursor (MetaDisplay *display)
 {
   MetaCursor cursor = display->current_cursor;
   MetaCursorSpriteXcursor *sprite_xcursor;
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaCursorTracker *cursor_tracker = meta_backend_get_cursor_tracker (backend);
 
   sprite_xcursor = meta_cursor_sprite_xcursor_new (cursor, cursor_tracker);
@@ -1882,7 +1900,7 @@ meta_display_begin_grab_op (MetaDisplay *display,
                             int          root_x,
                             int          root_y)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaWindow *grab_window = NULL;
   MetaEventRoute event_route;
 
@@ -1931,7 +1949,8 @@ meta_display_begin_grab_op (MetaDisplay *display,
   if (pointer_already_grabbed)
     display->grab_have_pointer = TRUE;
 
-  if (META_IS_BACKEND_X11 (meta_get_backend ()) && display->x11_display)
+  if (META_IS_BACKEND_X11 (backend_from_display (display)) &&
+      display->x11_display)
     {
       /* Since grab operations often happen as a result of implicit
        * pointer operations on the display X11 connection, we need
@@ -2046,7 +2065,7 @@ meta_display_end_grab_op (MetaDisplay *display,
 
   if (display->grab_have_pointer)
     {
-      MetaBackend *backend = meta_get_backend ();
+      MetaBackend *backend = backend_from_display (display);
       meta_backend_ungrab_device (backend, META_VIRTUAL_CORE_POINTER_ID, timestamp);
     }
 
@@ -2896,7 +2915,7 @@ meta_display_get_size (MetaDisplay *display,
                        int         *width,
                        int         *height)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   int display_width, display_height;
@@ -3015,7 +3034,7 @@ meta_display_request_pad_osd (MetaDisplay        *display,
                               ClutterInputDevice *pad,
                               gboolean            edition_mode)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaInputMapper *input_mapper;
   const gchar *layout_path = NULL;
   ClutterActor *osd;
@@ -3032,7 +3051,7 @@ meta_display_request_pad_osd (MetaDisplay        *display,
   if (display->current_pad_osd)
     return;
 
-  input_mapper = meta_backend_get_input_mapper (meta_get_backend ());
+  input_mapper = meta_backend_get_input_mapper (backend_from_display (display));
 
   if (input_mapper)
     {
@@ -3086,7 +3105,7 @@ meta_display_get_pad_action_label (MetaDisplay        *display,
       MetaWaylandTabletSeat *tablet_seat;
       MetaWaylandTabletPad *tablet_pad = NULL;
 
-      compositor = meta_wayland_compositor_get_default ();
+      compositor = wayland_compositor_from_display (display);
       tablet_seat = meta_wayland_tablet_manager_ensure_seat (compositor->tablet_manager,
                                                              compositor->seat);
       if (tablet_seat)
@@ -3124,7 +3143,7 @@ lookup_tablet_monitor (MetaDisplay        *display,
   MetaLogicalMonitor *monitor;
   gint monitor_idx = -1;
 
-  input_mapper = meta_backend_get_input_mapper (meta_get_backend ());
+  input_mapper = meta_backend_get_input_mapper (backend_from_display (display));
   if (!input_mapper)
     return -1;
 
@@ -3488,7 +3507,7 @@ static gboolean
 check_fullscreen_func (gpointer data)
 {
   MetaDisplay *display = data;
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   GList *logical_monitors, *l;
@@ -3605,7 +3624,7 @@ int
 meta_display_get_monitor_index_for_rect (MetaDisplay   *display,
                                          MetaRectangle *rect)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -3623,7 +3642,7 @@ meta_display_get_monitor_neighbor_index (MetaDisplay         *display,
                                          int                  which_monitor,
                                          MetaDisplayDirection direction)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -3649,7 +3668,7 @@ meta_display_get_monitor_neighbor_index (MetaDisplay         *display,
 int
 meta_display_get_current_monitor (MetaDisplay *display)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaLogicalMonitor *logical_monitor;
 
   logical_monitor = meta_backend_get_current_logical_monitor (backend);
@@ -3672,7 +3691,7 @@ meta_display_get_current_monitor (MetaDisplay *display)
 int
 meta_display_get_n_monitors (MetaDisplay *display)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
 
@@ -3692,7 +3711,7 @@ meta_display_get_n_monitors (MetaDisplay *display)
 int
 meta_display_get_primary_monitor (MetaDisplay *display)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -3720,7 +3739,7 @@ meta_display_get_monitor_geometry (MetaDisplay   *display,
                                    int            monitor,
                                    MetaRectangle *geometry)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -3752,7 +3771,7 @@ float
 meta_display_get_monitor_scale (MetaDisplay *display,
                                 int          monitor)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -3788,7 +3807,7 @@ gboolean
 meta_display_get_monitor_in_fullscreen (MetaDisplay *display,
                                         int          monitor)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_display (display);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
diff --git a/src/core/events.c b/src/core/events.c
index ecb87a9c2..00dee866a 100644
--- a/src/core/events.c
+++ b/src/core/events.c
@@ -231,11 +231,12 @@ meta_display_handle_event (MetaDisplay        *display,
   MetaGestureTracker *gesture_tracker;
   ClutterEventSequence *sequence;
   gboolean has_grab;
+#ifdef HAVE_WAYLAND
+  MetaWaylandCompositor *wayland_compositor;
+#endif
 
 #ifdef HAVE_WAYLAND
-  MetaWaylandCompositor *wayland_compositor = NULL;
-  if (meta_is_wayland_compositor ())
-    wayland_compositor = meta_wayland_compositor_get_default ();
+  wayland_compositor = meta_context_get_wayland_compositor (context);
 #endif
 
   has_grab = stage_has_grab (display);
diff --git a/src/core/keybindings.c b/src/core/keybindings.c
index 17c5fe75b..8ff61a94c 100644
--- a/src/core/keybindings.c
+++ b/src/core/keybindings.c
@@ -1420,6 +1420,10 @@ meta_change_keygrab (MetaKeyBindingManager *keys,
                      gboolean               grab,
                      MetaResolvedKeyCombo  *resolved_combo)
 {
+  MetaBackendX11 *backend_x11;
+  Display *xdisplay;
+  GArray *mods;
+  int i;
   unsigned char mask_bits[XIMaskLen (XI_LASTEVENT)] = { 0 };
   XIEventMask mask = { XIAllMasterDevices, sizeof (mask_bits), mask_bits };
 
@@ -1429,10 +1433,8 @@ meta_change_keygrab (MetaKeyBindingManager *keys,
   if (meta_is_wayland_compositor ())
     return;
 
-  MetaBackendX11 *backend = META_BACKEND_X11 (meta_get_backend ());
-  Display *xdisplay = meta_backend_x11_get_xdisplay (backend);
-  GArray *mods;
-  int i;
+  backend_x11 = META_BACKEND_X11 (keys->backend);
+  xdisplay = meta_backend_x11_get_xdisplay (backend_x11);
 
   /* Grab keycode/modmask, together with
    * all combinations of ignored modifiers.
@@ -1753,10 +1755,13 @@ meta_display_ungrab_accelerator (MetaDisplay *display,
 }
 
 static gboolean
-grab_keyboard (Window  xwindow,
-               guint32 timestamp,
-               int     grab_mode)
+grab_keyboard (MetaBackend *backend,
+               Window       xwindow,
+               uint32_t     timestamp,
+               int          grab_mode)
 {
+  MetaBackendX11 *backend_x11;
+  Display *xdisplay;
   int grab_status;
 
   unsigned char mask_bits[XIMaskLen (XI_LASTEVENT)] = { 0 };
@@ -1772,8 +1777,8 @@ grab_keyboard (Window  xwindow,
    * presses
    */
 
-  MetaBackendX11 *backend = META_BACKEND_X11 (meta_get_backend ());
-  Display *xdisplay = meta_backend_x11_get_xdisplay (backend);
+  backend_x11 = META_BACKEND_X11 (backend);
+  xdisplay = meta_backend_x11_get_xdisplay (backend_x11);
 
   /* Strictly, we only need to set grab_mode on the keyboard device
    * while the pointer should always be XIGrabModeAsync. Unfortunately
@@ -1797,13 +1802,17 @@ grab_keyboard (Window  xwindow,
 }
 
 static void
-ungrab_keyboard (guint32 timestamp)
+ungrab_keyboard (MetaBackend *backend,
+                 uint32_t     timestamp)
 {
+  MetaBackendX11 *backend_x11;
+  Display *xdisplay;
+
   if (meta_is_wayland_compositor ())
     return;
 
-  MetaBackendX11 *backend = META_BACKEND_X11 (meta_get_backend ());
-  Display *xdisplay = meta_backend_x11_get_xdisplay (backend);
+  backend_x11 = META_BACKEND_X11 (backend);
+  xdisplay = meta_backend_x11_get_xdisplay (backend_x11);
 
   XIUngrabDevice (xdisplay, META_VIRTUAL_CORE_KEYBOARD_ID, timestamp);
 }
@@ -1812,6 +1821,9 @@ gboolean
 meta_window_grab_all_keys (MetaWindow  *window,
                            guint32      timestamp)
 {
+  MetaDisplay *display = meta_window_get_display (window);
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   Window grabwindow;
   gboolean retval = TRUE;
 
@@ -1835,7 +1847,7 @@ meta_window_grab_all_keys (MetaWindow  *window,
 
       meta_topic (META_DEBUG_KEYBINDINGS,
                   "Grabbing all keys on window %s", window->desc);
-      retval = grab_keyboard (grabwindow, timestamp, XIGrabModeAsync);
+      retval = grab_keyboard (backend, grabwindow, timestamp, XIGrabModeAsync);
     }
   if (retval)
     {
@@ -1854,7 +1866,13 @@ meta_window_ungrab_all_keys (MetaWindow *window,
   if (window->all_keys_grabbed)
     {
       if (!meta_is_wayland_compositor())
-        ungrab_keyboard (timestamp);
+        {
+          MetaDisplay *display = meta_window_get_display (window);
+          MetaContext *context = meta_display_get_context (display);
+          MetaBackend *backend = meta_context_get_backend (context);
+
+          ungrab_keyboard (backend, timestamp);
+        }
 
       window->grab_on_frame = FALSE;
       window->all_keys_grabbed = FALSE;
@@ -1868,25 +1886,30 @@ meta_window_ungrab_all_keys (MetaWindow *window,
 void
 meta_display_freeze_keyboard (MetaDisplay *display, guint32 timestamp)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
 
   if (!META_IS_BACKEND_X11 (backend))
     return;
 
   Window window = meta_backend_x11_get_xwindow (META_BACKEND_X11 (backend));
-  grab_keyboard (window, timestamp, XIGrabModeSync);
+  grab_keyboard (backend, window, timestamp, XIGrabModeSync);
 }
 
 void
 meta_display_ungrab_keyboard (MetaDisplay *display, guint32 timestamp)
 {
-  ungrab_keyboard (timestamp);
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
+
+  ungrab_keyboard (backend, timestamp);
 }
 
 void
 meta_display_unfreeze_keyboard (MetaDisplay *display, guint32 timestamp)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
 
   if (!META_IS_BACKEND_X11 (backend))
     return;
@@ -2259,7 +2282,9 @@ process_key_event (MetaDisplay     *display,
     }
 
   {
-    MetaBackend *backend = meta_get_backend ();
+    MetaContext *context = meta_display_get_context (display);
+    MetaBackend *backend = meta_context_get_backend (context);
+
     if (META_IS_BACKEND_X11 (backend))
       {
         Display *xdisplay = meta_backend_x11_get_xdisplay (META_BACKEND_X11 (backend));
@@ -3473,7 +3498,8 @@ handle_move_to_monitor (MetaDisplay    *display,
                         MetaKeyBinding *binding,
                         gpointer        dummy)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   gint which = binding->handler->data;
@@ -3594,7 +3620,8 @@ handle_switch_monitor (MetaDisplay    *display,
                        MetaKeyBinding *binding,
                        gpointer        dummy)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaMonitorSwitchConfigType config_type =
@@ -3614,7 +3641,8 @@ handle_rotate_monitor (MetaDisplay    *display,
                        MetaKeyBinding *binding,
                        gpointer        dummy)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
 
@@ -3949,7 +3977,8 @@ init_builtin_key_bindings (MetaDisplay *display)
                           handle_rotate_monitor, 0);
 
 #ifdef HAVE_NATIVE_BACKEND
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   if (META_IS_BACKEND_NATIVE (backend))
     {
       add_builtin_keybinding (display,
@@ -4452,7 +4481,8 @@ void
 meta_display_init_keys (MetaDisplay *display)
 {
   MetaKeyBindingManager *keys = &display->key_binding_manager;
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaKeyHandler *handler;
 
   keys->backend = backend;
diff --git a/src/core/meta-clipboard-manager.c b/src/core/meta-clipboard-manager.c
index 794195f41..b84550176 100644
--- a/src/core/meta-clipboard-manager.c
+++ b/src/core/meta-clipboard-manager.c
@@ -22,6 +22,7 @@
 #include "config.h"
 
 #include "core/meta-clipboard-manager.h"
+#include "core/meta-selection-private.h"
 #include "meta/meta-selection-source-memory.h"
 
 #define MAX_TEXT_SIZE (4 * 1024 * 1024) /* 4MB */
@@ -68,7 +69,7 @@ transfer_cb (MetaSelection *selection,
              GAsyncResult  *result,
              GOutputStream *output)
 {
-  MetaDisplay *display = meta_get_display ();
+  MetaDisplay *display = meta_selection_get_display (selection);
   GError *error = NULL;
 
   if (!meta_selection_transfer_finish (selection, result, &error))
diff --git a/src/core/meta-context-main.c b/src/core/meta-context-main.c
index 5baa7c9f5..8fee10cd5 100644
--- a/src/core/meta-context-main.c
+++ b/src/core/meta-context-main.c
@@ -343,7 +343,8 @@ static gboolean
 add_persistent_virtual_monitors (MetaContextMain  *context_main,
                                  GError          **error)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = META_CONTEXT (context_main);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   GList *l;
diff --git a/src/core/meta-launch-context.c b/src/core/meta-launch-context.c
index cccba79f1..7eaf05e38 100644
--- a/src/core/meta-launch-context.c
+++ b/src/core/meta-launch-context.c
@@ -176,6 +176,7 @@ meta_launch_context_get_startup_notify_id (GAppLaunchContext *launch_context,
 
       sn = meta_display_get_startup_notification (context->display);
       seq = g_object_new (META_TYPE_STARTUP_SEQUENCE,
+                          "display", context->display,
                           "id", startup_id,
                           "application-id", application_id,
                           "name", g_app_info_get_name (info),
diff --git a/src/core/meta-selection-private.h b/src/core/meta-selection-private.h
index de9caf9bf..5c04849f7 100644
--- a/src/core/meta-selection-private.h
+++ b/src/core/meta-selection-private.h
@@ -29,4 +29,6 @@ MetaSelectionSource *
   meta_selection_get_current_owner (MetaSelection     *selection,
                                     MetaSelectionType  selection_type);
 
+MetaDisplay * meta_selection_get_display (MetaSelection *selection);
+
 #endif /* META_SELECTION_PRIVATE_H */
diff --git a/src/core/meta-selection.c b/src/core/meta-selection.c
index 411db4971..849f21240 100644
--- a/src/core/meta-selection.c
+++ b/src/core/meta-selection.c
@@ -488,3 +488,9 @@ meta_selection_get_current_owner (MetaSelection     *selection,
 
   return selection->owners[selection_type];
 }
+
+MetaDisplay *
+meta_selection_get_display (MetaSelection *selection)
+{
+  return selection->display;
+}
diff --git a/src/core/place.c b/src/core/place.c
index 1075fe20d..f692214cf 100644
--- a/src/core/place.c
+++ b/src/core/place.c
@@ -84,7 +84,9 @@ find_next_cascade (MetaWindow *window,
                    int        *new_x,
                    int        *new_y)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaDisplay *display = meta_window_get_display (window);
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   GList *tmp;
   GList *sorted;
   int cascade_x, cascade_y;
@@ -665,7 +667,9 @@ meta_window_place (MetaWindow        *window,
                    int               *new_x,
                    int               *new_y)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaDisplay *display = meta_window_get_display (window);
+  MetaContext *context = meta_display_get_context (display);
+  MetaBackend *backend = meta_context_get_backend (context);
   GList *windows = NULL;
   MetaLogicalMonitor *logical_monitor;
 
diff --git a/src/core/stack-tracker.c b/src/core/stack-tracker.c
index 9c217a08c..24d5d25db 100644
--- a/src/core/stack-tracker.c
+++ b/src/core/stack-tracker.c
@@ -584,7 +584,13 @@ void
 meta_stack_tracker_free (MetaStackTracker *tracker)
 {
   if (tracker->sync_stack_later)
-    meta_later_remove (tracker->sync_stack_later);
+    {
+      MetaCompositor *compositor =
+        meta_display_get_compositor (tracker->display);
+      MetaLaters *laters = meta_compositor_get_laters (compositor);
+
+      meta_laters_remove (laters, tracker->sync_stack_later);
+    }
 
   g_array_free (tracker->verified_stack, TRUE);
   if (tracker->predicted_stack)
@@ -919,7 +925,10 @@ meta_stack_tracker_sync_stack (MetaStackTracker *tracker)
 
   if (tracker->sync_stack_later)
     {
-      meta_later_remove (tracker->sync_stack_later);
+      MetaLaters *laters;
+
+      laters = meta_compositor_get_laters (tracker->display->compositor);
+      meta_laters_remove (laters, tracker->sync_stack_later);
       tracker->sync_stack_later = 0;
     }
 
@@ -987,12 +996,15 @@ stack_tracker_sync_stack_later (gpointer data)
 void
 meta_stack_tracker_queue_sync_stack (MetaStackTracker *tracker)
 {
-  if (tracker->sync_stack_later == 0)
-    {
-      tracker->sync_stack_later = meta_later_add (META_LATER_SYNC_STACK,
-                                                  stack_tracker_sync_stack_later,
-                                                  tracker, NULL);
-    }
+  MetaLaters *laters;
+
+  if (tracker->sync_stack_later != 0)
+    return;
+
+  laters = meta_compositor_get_laters (tracker->display->compositor);
+  tracker->sync_stack_later = meta_laters_add (laters, META_LATER_SYNC_STACK,
+                                               stack_tracker_sync_stack_later,
+                                               tracker, NULL);
 }
 
 /* When moving an X window we sometimes need an X based sibling.
diff --git a/src/core/startup-notification-private.h b/src/core/startup-notification-private.h
index 5bdf2ac1a..608ca6852 100644
--- a/src/core/startup-notification-private.h
+++ b/src/core/startup-notification-private.h
@@ -49,4 +49,6 @@ MetaStartupSequence *
          meta_startup_notification_lookup_sequence (MetaStartupNotification *sn,
                                                     const gchar             *id);
 
+MetaDisplay * meta_startup_sequence_get_display (MetaStartupSequence *seq);
+
 #endif /* META_STARTUP_NOTIFICATION_PRIVATE_H */
diff --git a/src/core/startup-notification.c b/src/core/startup-notification.c
index bf46f43d3..371ec35ff 100644
--- a/src/core/startup-notification.c
+++ b/src/core/startup-notification.c
@@ -49,6 +49,7 @@ enum
 enum
 {
   PROP_SEQ_0,
+  PROP_SEQ_DISPLAY,
   PROP_SEQ_ID,
   PROP_SEQ_TIMESTAMP,
   PROP_SEQ_ICON_NAME,
@@ -93,7 +94,10 @@ struct _MetaStartupNotification
   guint startup_sequence_timeout_id;
 };
 
-typedef struct {
+typedef struct
+{
+  MetaDisplay *display;
+
   char *wmclass;
   char *name;
   char *application_id;
@@ -183,6 +187,9 @@ meta_startup_sequence_set_property (GObject      *object,
 
   switch (prop_id)
     {
+    case PROP_SEQ_DISPLAY:
+      priv->display = g_value_get_object (value);
+      break;
     case PROP_SEQ_ID:
       priv->id = g_value_dup_string (value);
       break;
@@ -224,6 +231,9 @@ meta_startup_sequence_get_property (GObject    *object,
 
   switch (prop_id)
     {
+    case PROP_SEQ_DISPLAY:
+      g_value_set_object (value, priv->display);
+      break;
     case PROP_SEQ_ID:
       g_value_set_string (value, priv->id);
       break;
@@ -275,6 +285,13 @@ meta_startup_sequence_class_init (MetaStartupSequenceClass *klass)
                   0, NULL, NULL, NULL,
                   G_TYPE_NONE, 0);
 
+  seq_props[PROP_SEQ_DISPLAY] =
+    g_param_spec_object ("display",
+                         "Display",
+                         "Display",
+                         META_TYPE_DISPLAY,
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY);
   seq_props[PROP_SEQ_ID] =
     g_param_spec_string ("id",
                          "ID",
@@ -455,6 +472,17 @@ meta_startup_sequence_get_wmclass (MetaStartupSequence *seq)
   return priv->wmclass;
 }
 
+MetaDisplay *
+meta_startup_sequence_get_display (MetaStartupSequence *seq)
+{
+  MetaStartupSequencePrivate *priv;
+
+  g_return_val_if_fail (META_IS_STARTUP_SEQUENCE (seq), NULL);
+
+  priv = meta_startup_sequence_get_instance_private (seq);
+  return priv->display;
+}
+
 static void
 on_sequence_completed (MetaStartupSequence     *seq,
                        MetaStartupNotification *sn)
diff --git a/src/core/window.c b/src/core/window.c
index f11ea7351..d046d505c 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -224,6 +224,15 @@ enum
 
 static guint window_signals[LAST_SIGNAL] = { 0 };
 
+static MetaBackend *
+backend_from_window (MetaWindow *window)
+{
+  MetaDisplay *display = meta_window_get_display (window);
+  MetaContext *context = meta_display_get_context (display);
+
+  return meta_context_get_backend (context);
+}
+
 static void
 prefs_changed_callback (MetaPreference pref,
                         gpointer       data)
@@ -986,7 +995,7 @@ meta_window_main_monitor_changed (MetaWindow               *window,
 MetaLogicalMonitor *
 meta_window_find_monitor_from_frame_rect (MetaWindow *window)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_window (window);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaRectangle window_rect;
@@ -3634,7 +3643,7 @@ static MetaLogicalMonitor *
 find_monitor_by_winsys_id (MetaWindow *window,
                            uint64_t    winsys_id)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_window (window);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   GList *logical_monitors, *l;
@@ -4626,7 +4635,7 @@ meta_window_focus (MetaWindow  *window,
         }
     }
 
-  backend = meta_get_backend ();
+  backend = backend_from_window (window);
   stage = CLUTTER_STAGE (meta_backend_get_stage (backend));
 
   if (window->display->event_route == META_EVENT_ROUTE_NORMAL &&
@@ -5771,7 +5780,7 @@ update_move_maybe_tile (MetaWindow *window,
                         int         x,
                         int         y)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_window (window);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -5927,7 +5936,7 @@ update_move (MetaWindow              *window,
   else if ((window->shaken_loose || META_WINDOW_MAXIMIZED (window)) &&
            window->tile_mode != META_TILE_LEFT && window->tile_mode != META_TILE_RIGHT)
     {
-      MetaBackend *backend = meta_get_backend ();
+      MetaBackend *backend = backend_from_window (window);
       MetaMonitorManager *monitor_manager =
         meta_backend_get_monitor_manager (backend);
       int n_logical_monitors;
@@ -6418,7 +6427,7 @@ meta_window_get_work_area_for_monitor (MetaWindow    *window,
                                        int            which_monitor,
                                        MetaRectangle *area)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_window (window);
   MetaMonitorManager *monitor_manager = meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
 
@@ -8106,7 +8115,7 @@ window_has_pointer_wayland (MetaWindow *window)
 
   seat = clutter_backend_get_default_seat (clutter_get_default_backend ());
   dev = clutter_seat_get_pointer (seat);
-  stage = CLUTTER_STAGE (meta_backend_get_stage (meta_get_backend ()));
+  stage = CLUTTER_STAGE (meta_backend_get_stage (backend_from_window (window)));
   pointer_actor = clutter_stage_get_device_actor (stage, dev, NULL);
   window_actor = CLUTTER_ACTOR (meta_window_get_compositor_private (window));
 
@@ -8151,7 +8160,7 @@ window_focus_on_pointer_rest_callback (gpointer data)
   MetaFocusData *focus_data = data;
   MetaWindow *window = focus_data->window;
   MetaDisplay *display = window->display;
-  MetaBackend *backend = meta_get_backend ();
+  MetaBackend *backend = backend_from_window (window);
   MetaCursorTracker *cursor_tracker = meta_backend_get_cursor_tracker (backend);
   graphene_point_t point;
   guint32 timestamp;
diff --git a/src/core/workspace.c b/src/core/workspace.c
index e933995f3..5e7b325b1 100644
--- a/src/core/workspace.c
+++ b/src/core/workspace.c
@@ -850,7 +850,8 @@ copy_strut_list(GSList *original)
 static void
 ensure_work_areas_validated (MetaWorkspace *workspace)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (workspace->display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   GList *windows;
@@ -1070,7 +1071,8 @@ void
 meta_workspace_set_builtin_struts (MetaWorkspace *workspace,
                                    GSList        *struts)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (workspace->display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaDisplay *display = workspace->display;
@@ -1163,7 +1165,8 @@ meta_workspace_get_work_area_for_monitor (MetaWorkspace *workspace,
                                           int            which_monitor,
                                           MetaRectangle *area)
 {
-  MetaBackend *backend = meta_get_backend();
+  MetaContext *context = meta_display_get_context (workspace->display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaMonitorManager *monitor_manager =
     meta_backend_get_monitor_manager (backend);
   MetaLogicalMonitor *logical_monitor;
@@ -1550,7 +1553,8 @@ static MetaWindow *
 get_pointer_window (MetaWorkspace *workspace,
                     MetaWindow    *not_this_one)
 {
-  MetaBackend *backend = meta_get_backend ();
+  MetaContext *context = meta_display_get_context (workspace->display);
+  MetaBackend *backend = meta_context_get_backend (context);
   MetaCursorTracker *cursor_tracker = meta_backend_get_cursor_tracker (backend);
   graphene_point_t point;
 
diff --git a/src/wayland/meta-wayland-activation.c b/src/wayland/meta-wayland-activation.c
index 89f7ca221..ae4596bbd 100644
--- a/src/wayland/meta-wayland-activation.c
+++ b/src/wayland/meta-wayland-activation.c
@@ -56,6 +56,15 @@ struct _MetaXdgActivationToken
   gboolean committed;
 };
 
+static MetaDisplay *
+display_from_activation (MetaWaylandActivation *activation)
+{
+  MetaContext *context =
+    meta_wayland_compositor_get_context (activation->compositor);
+
+  return meta_context_get_display (context);
+}
+
 static void
 unbind_resource (struct wl_resource *resource)
 {
@@ -104,7 +113,7 @@ sequence_complete_cb (MetaStartupSequence    *sequence,
                       MetaXdgActivationToken *token)
 {
   MetaWaylandActivation *activation = token->activation;
-  MetaDisplay *display = meta_get_display ();
+  MetaDisplay *display = meta_startup_sequence_get_display (sequence);
 
   if (!g_hash_table_contains (activation->tokens, token->token))
     return;
@@ -148,7 +157,7 @@ token_commit (struct wl_client   *client,
 {
   MetaXdgActivationToken *token = wl_resource_get_user_data (resource);
   MetaWaylandActivation *activation = token->activation;
-  MetaDisplay *display = meta_get_display ();
+  MetaDisplay *display = display_from_activation (activation);
   uint64_t timestamp;
 
   if (token->committed)
@@ -164,6 +173,7 @@ token_commit (struct wl_client   *client,
   token->committed = TRUE;
   token->token = create_startup_token (activation, display);
   token->sequence = g_object_new (META_TYPE_STARTUP_SEQUENCE,
+                                  "display", display,
                                   "id", token->token,
                                   "application-id", token->app_id,
                                   "timestamp", timestamp,
@@ -321,7 +331,7 @@ activation_activate (struct wl_client   *client,
 {
   MetaWaylandActivation *activation = wl_resource_get_user_data (resource);
   MetaWaylandSurface *surface = wl_resource_get_user_data (surface_resource);
-  MetaDisplay *display = meta_get_display ();
+  MetaDisplay *display = display_from_activation (activation);
   MetaXdgActivationToken *token;
   MetaStartupSequence *sequence;
   MetaWindow *window;
diff --git a/src/wayland/meta-wayland-gtk-shell.c b/src/wayland/meta-wayland-gtk-shell.c
index 5fd1d80cf..b7e891f05 100644
--- a/src/wayland/meta-wayland-gtk-shell.c
+++ b/src/wayland/meta-wayland-gtk-shell.c
@@ -47,6 +47,8 @@ struct _MetaWaylandGtkShell
 {
   GObject parent;
 
+  MetaWaylandCompositor *compositor;
+
   GList *shell_resources;
   uint32_t capabilities;
 };
@@ -170,7 +172,9 @@ gtk_surface_request_focus (struct wl_client   *client,
 {
   MetaWaylandGtkSurface *gtk_surface = wl_resource_get_user_data (resource);
   MetaWaylandSurface *surface = gtk_surface->surface;
-  MetaDisplay *display = meta_get_display ();
+  MetaContext *context =
+    meta_wayland_compositor_get_context (surface->compositor);
+  MetaDisplay *display = meta_context_get_display (context);
   MetaStartupSequence *sequence = NULL;
   MetaWindow *window;
 
@@ -491,10 +495,11 @@ gtk_shell_set_startup_id (struct wl_client   *client,
                           struct wl_resource *resource,
                           const char         *startup_id)
 {
+  MetaWaylandGtkShell *gtk_shell = wl_resource_get_user_data (resource);
+  MetaContext *context =
+    meta_wayland_compositor_get_context (gtk_shell->compositor);
+  MetaDisplay *display = meta_context_get_display (context);
   MetaStartupSequence *sequence;
-  MetaDisplay *display;
-
-  display = meta_get_display ();
 
   sequence = meta_startup_notification_lookup_sequence (display->startup_notification,
                                                         startup_id);
@@ -548,6 +553,7 @@ gtk_shell_notify_launch (struct wl_client   *client,
 
   timestamp = meta_display_get_current_time_roundtrip (display);
   sequence = g_object_new (META_TYPE_STARTUP_SEQUENCE,
+                           "display", display,
                            "id", startup_id,
                            "timestamp", timestamp,
                            NULL);
@@ -652,6 +658,7 @@ meta_wayland_gtk_shell_new (MetaWaylandCompositor *compositor)
                         gtk_shell, bind_gtk_shell) == NULL)
     g_error ("Failed to register a global gtk-shell object");
 
+  gtk_shell->compositor = compositor;
   gtk_shell->capabilities = calculate_capabilities ();
 
   meta_prefs_add_listener (prefs_changed, gtk_shell);
diff --git a/src/x11/meta-startup-notification-x11.c b/src/x11/meta-startup-notification-x11.c
index f0f1a63ff..27ad8bd0a 100644
--- a/src/x11/meta-startup-notification-x11.c
+++ b/src/x11/meta-startup-notification-x11.c
@@ -149,12 +149,14 @@ meta_startup_sequence_x11_class_init (MetaStartupSequenceX11Class *klass)
 }
 
 static MetaStartupSequence *
-meta_startup_sequence_x11_new (SnStartupSequence *seq)
+meta_startup_sequence_x11_new (MetaDisplay       *display,
+                               SnStartupSequence *seq)
 {
   gint64 timestamp;
 
   timestamp = sn_startup_sequence_get_timestamp (seq);
   return g_object_new (META_TYPE_STARTUP_SEQUENCE_X11,
+                       "display", display,
                        "id", sn_startup_sequence_get_id (seq),
                        "icon-name", sn_startup_sequence_get_icon_name (seq),
                        "application-id", sn_startup_sequence_get_application_id (seq),
@@ -193,7 +195,8 @@ meta_startup_notification_sn_event (SnMonitorEvent *event,
                                     void           *user_data)
 {
   MetaX11Display *x11_display = user_data;
-  MetaStartupNotification *sn = x11_display->display->startup_notification;
+  MetaDisplay *display = meta_x11_display_get_display (x11_display);
+  MetaStartupNotification *sn = display->startup_notification;
   MetaStartupSequence *seq;
   SnStartupSequence *sequence;
 
@@ -214,7 +217,7 @@ meta_startup_notification_sn_event (SnMonitorEvent *event,
                     sn_startup_sequence_get_id (sequence),
                     wmclass ? wmclass : "(unset)");
 
-        seq = meta_startup_sequence_x11_new (sequence);
+        seq = meta_startup_sequence_x11_new (display, sequence);
         meta_startup_notification_add_sequence (sn, seq);
         g_object_unref (seq);
       }