gtk: Stop setting GDK_EXPOSURE_MASK on random widgets

These days exposure happens only on the native windows (generally the
toplevel window) and is propagated down recursively. The expose event
is only useful for backwards compat, and in fact, for double buffered
widgets we totally ignore the event (and non-double buffering breaks
on wayland).

So, by not setting the mask we avoid emitting these events and then
later ignoring them.

We still keep it on eventbox, fixed and layout as these are used
in weird ways that want backwards compat.

24 files changed, 26 insertions, 38 deletions

diff --git a/gtk/deprecated/gtkcolorsel.c b/gtk/deprecated/gtkcolorsel.c
index c0d358b6d6..17fe82029e 100644
--- a/gtk/deprecated/gtkcolorsel.c
+++ b/gtk/deprecated/gtkcolorsel.c
@@ -1659,7 +1659,6 @@ palette_new (GtkColorSelection *colorsel)
   g_object_set_data (G_OBJECT (retval), I_("color_set"), GINT_TO_POINTER (0));
   gtk_widget_set_events (retval, GDK_BUTTON_PRESS_MASK
                          | GDK_BUTTON_RELEASE_MASK
-                         | GDK_EXPOSURE_MASK
                          | GDK_ENTER_NOTIFY_MASK
                          | GDK_LEAVE_NOTIFY_MASK);
 
diff --git a/gtk/deprecated/gtkhandlebox.c b/gtk/deprecated/gtkhandlebox.c
index 76f6e6107b..f254138763 100644
--- a/gtk/deprecated/gtkhandlebox.c
+++ b/gtk/deprecated/gtkhandlebox.c
@@ -494,8 +494,7 @@ gtk_handle_box_realize (GtkWidget *widget)
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
-  attributes.event_mask = (gtk_widget_get_events (widget)
-                           | GDK_EXPOSURE_MASK);
+  attributes.event_mask = gtk_widget_get_events (widget);
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 
   window = gdk_window_new (gtk_widget_get_parent_window (widget),
@@ -509,7 +508,6 @@ gtk_handle_box_realize (GtkWidget *widget)
   attributes.height = allocation.height;
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.event_mask = (gtk_widget_get_events (widget)
-                           | GDK_EXPOSURE_MASK
                            | GDK_BUTTON1_MOTION_MASK
                            | GDK_POINTER_MOTION_HINT_MASK
                            | GDK_BUTTON_PRESS_MASK
diff --git a/gtk/deprecated/gtkmisc.c b/gtk/deprecated/gtkmisc.c
index 55eca88ba9..8ad92f09ab 100644
--- a/gtk/deprecated/gtkmisc.c
+++ b/gtk/deprecated/gtkmisc.c
@@ -440,7 +440,7 @@ gtk_misc_realize (GtkWidget *widget)
       attributes.height = allocation.height;
       attributes.wclass = GDK_INPUT_OUTPUT;
       attributes.visual = gtk_widget_get_visual (widget);
-      attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+      attributes.event_mask = gtk_widget_get_events (widget);
       attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 
       window = gdk_window_new (gtk_widget_get_parent_window (widget), &attributes, attributes_mask);
diff --git a/gtk/gtkcalendar.c b/gtk/gtkcalendar.c
index 894cd6b85a..42157c2a1e 100644
--- a/gtk/gtkcalendar.c
+++ b/gtk/gtkcalendar.c
@@ -1638,7 +1638,6 @@ gtk_calendar_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_ONLY;
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.event_mask = (gtk_widget_get_events (widget)
-                           | GDK_EXPOSURE_MASK
                            | GDK_SCROLL_MASK
                            | GDK_BUTTON_PRESS_MASK
                            | GDK_BUTTON_RELEASE_MASK
diff --git a/gtk/gtkflowbox.c b/gtk/gtkflowbox.c
index 95d54c22f6..bfd1490155 100644
--- a/gtk/gtkflowbox.c
+++ b/gtk/gtkflowbox.c
@@ -3086,7 +3086,6 @@ gtk_flow_box_realize (GtkWidget *widget)
                                 | GDK_ENTER_NOTIFY_MASK
                                 | GDK_LEAVE_NOTIFY_MASK
                                 | GDK_POINTER_MOTION_MASK
-                                | GDK_EXPOSURE_MASK
                                 | GDK_KEY_PRESS_MASK
                                 | GDK_BUTTON_PRESS_MASK
                                 | GDK_BUTTON_RELEASE_MASK;
diff --git a/gtk/gtkglarea.c b/gtk/gtkglarea.c
index f357b10098..409840974a 100644
--- a/gtk/gtkglarea.c
+++ b/gtk/gtkglarea.c
@@ -284,7 +284,7 @@ gtk_gl_area_realize (GtkWidget *widget)
   attributes.width = allocation.width;
   attributes.height = allocation.height;
   attributes.wclass = GDK_INPUT_ONLY;
-  attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+  attributes.event_mask = gtk_widget_get_events (widget);
 
   attributes_mask = GDK_WA_X | GDK_WA_Y;
 
diff --git a/gtk/gtkiconview.c b/gtk/gtkiconview.c
index f81b9096cd..4dbf096353 100644
--- a/gtk/gtkiconview.c
+++ b/gtk/gtkiconview.c
@@ -1300,8 +1300,7 @@ gtk_icon_view_realize (GtkWidget *widget)
   attributes.y = 0;
   attributes.width = MAX (icon_view->priv->width, allocation.width);
   attributes.height = MAX (icon_view->priv->height, allocation.height);
-  attributes.event_mask = (GDK_EXPOSURE_MASK |
-                           GDK_SCROLL_MASK |
+  attributes.event_mask = (GDK_SCROLL_MASK |
                            GDK_SMOOTH_SCROLL_MASK |
                            GDK_POINTER_MOTION_MASK |
                            GDK_LEAVE_NOTIFY_MASK |
diff --git a/gtk/gtklistbox.c b/gtk/gtklistbox.c
index bc4a1e6200..66281f813a 100644
--- a/gtk/gtklistbox.c
+++ b/gtk/gtklistbox.c
@@ -2094,7 +2094,7 @@ gtk_list_box_realize (GtkWidget *widget)
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.event_mask = gtk_widget_get_events (widget) |
     GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK | GDK_POINTER_MOTION_MASK |
-    GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK;
+    GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK;
   attributes.wclass = GDK_INPUT_OUTPUT;
 
   window = gdk_window_new (gtk_widget_get_parent_window (widget),
diff --git a/gtk/gtkmagnifier.c b/gtk/gtkmagnifier.c
index 04f15bc961..e83d3066fe 100644
--- a/gtk/gtkmagnifier.c
+++ b/gtk/gtkmagnifier.c
@@ -298,8 +298,7 @@ _gtk_magnifier_init (GtkMagnifier *magnifier)
   priv = _gtk_magnifier_get_instance_private (magnifier);
 
   gtk_widget_set_events (widget,
-                         gtk_widget_get_events (widget) |
-                         GDK_EXPOSURE_MASK);
+                         gtk_widget_get_events (widget));
 
   gtk_widget_set_has_window (widget, FALSE);
   priv->magnification = 1;
diff --git a/gtk/gtkmenu.c b/gtk/gtkmenu.c
index b39de7dd2c..61f8541950 100644
--- a/gtk/gtkmenu.c
+++ b/gtk/gtkmenu.c
@@ -2582,7 +2582,7 @@ gtk_menu_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask = gtk_widget_get_events (widget);
-  attributes.event_mask |= (GDK_EXPOSURE_MASK | GDK_KEY_PRESS_MASK |
+  attributes.event_mask |= (GDK_KEY_PRESS_MASK |
                             GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK );
 
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
diff --git a/gtk/gtkmenushell.c b/gtk/gtkmenushell.c
index 80044ef3fe..a56e934bdf 100644
--- a/gtk/gtkmenushell.c
+++ b/gtk/gtkmenushell.c
@@ -602,8 +602,7 @@ gtk_menu_shell_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask = gtk_widget_get_events (widget);
-  attributes.event_mask |= (GDK_EXPOSURE_MASK |
-                            GDK_BUTTON_PRESS_MASK |
+  attributes.event_mask |= (GDK_BUTTON_PRESS_MASK |
                             GDK_BUTTON_RELEASE_MASK |
                             GDK_POINTER_MOTION_MASK |
                             GDK_KEY_PRESS_MASK |
diff --git a/gtk/gtknotebook.c b/gtk/gtknotebook.c
index 0f631b9764..8048dab4ff 100644
--- a/gtk/gtknotebook.c
+++ b/gtk/gtknotebook.c
@@ -3116,7 +3116,7 @@ show_drag_window (GtkNotebook        *notebook,
       attributes.window_type = GDK_WINDOW_CHILD;
       attributes.wclass = GDK_INPUT_OUTPUT;
       attributes.visual = gtk_widget_get_visual (widget);
-      attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK;
+      attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
       attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 
       priv->drag_window = gdk_window_new (gtk_widget_get_parent_window (widget),
diff --git a/gtk/gtkoverlay.c b/gtk/gtkoverlay.c
index 1cac3225a5..661f3d10d6 100644
--- a/gtk/gtkoverlay.c
+++ b/gtk/gtkoverlay.c
@@ -151,7 +151,7 @@ gtk_overlay_create_child_window (GtkOverlay *overlay,
   attributes.y = allocation.y;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
-  attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+  attributes.event_mask = gtk_widget_get_events (widget);
 
   window = gdk_window_new (gtk_widget_get_window (widget),
                            &attributes, attributes_mask);
diff --git a/gtk/gtkpaned.c b/gtk/gtkpaned.c
index e6d230c15f..f9fb9786aa 100644
--- a/gtk/gtkpaned.c
+++ b/gtk/gtkpaned.c
@@ -1526,7 +1526,7 @@ gtk_paned_create_child_window (GtkPaned  *paned,
 
   attributes.window_type = GDK_WINDOW_CHILD;
   attributes.wclass = GDK_INPUT_OUTPUT;
-  attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+  attributes.event_mask = gtk_widget_get_events (widget);
   attributes.visual = gtk_widget_get_visual (widget);
   if (child)
     {
diff --git a/gtk/gtkpopover.c b/gtk/gtkpopover.c
index 86eda36bf1..969717ba16 100644
--- a/gtk/gtkpopover.c
+++ b/gtk/gtkpopover.c
@@ -345,7 +345,6 @@ gtk_popover_realize (GtkWidget *widget)
     GDK_BUTTON_MOTION_MASK |
     GDK_BUTTON_PRESS_MASK |
     GDK_BUTTON_RELEASE_MASK |
-    GDK_EXPOSURE_MASK |
     GDK_ENTER_NOTIFY_MASK |
     GDK_LEAVE_NOTIFY_MASK;
 
diff --git a/gtk/gtkrevealer.c b/gtk/gtkrevealer.c
index 20ff0dcc63..424840aec3 100644
--- a/gtk/gtkrevealer.c
+++ b/gtk/gtkrevealer.c
@@ -367,7 +367,7 @@ gtk_revealer_real_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask =
-    gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+    gtk_widget_get_events (widget);
   attributes_mask = (GDK_WA_X | GDK_WA_Y) | GDK_WA_VISUAL;
 
   priv->view_window =
diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index bc29e9d1bd..c97a6f2c6d 100644
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -3936,7 +3936,7 @@ create_indicator_window (GtkScrolledWindow *scrolled_window,
   attributes.y = allocation.y;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
-  attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+  attributes.event_mask = gtk_widget_get_events (widget);
 
   window = gdk_window_new (gtk_widget_get_window (widget),
                            &attributes, attributes_mask);
@@ -4226,7 +4226,7 @@ gtk_scrolled_window_realize (GtkWidget *widget)
   attributes.y = allocation.y;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
-  attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK |
+  attributes.event_mask = gtk_widget_get_events (widget) |
     GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
 
   window = gdk_window_new (gtk_widget_get_parent_window (widget),
diff --git a/gtk/gtkspinbutton.c b/gtk/gtkspinbutton.c
index 649ad5af42..bac8bdeb23 100644
--- a/gtk/gtkspinbutton.c
+++ b/gtk/gtkspinbutton.c
@@ -1093,7 +1093,7 @@ gtk_spin_button_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_ONLY;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask = gtk_widget_get_events (widget);
-  attributes.event_mask |= GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK
+  attributes.event_mask |= GDK_BUTTON_PRESS_MASK
     | GDK_BUTTON_RELEASE_MASK | GDK_LEAVE_NOTIFY_MASK | GDK_ENTER_NOTIFY_MASK
     | GDK_POINTER_MOTION_MASK;
 
diff --git a/gtk/gtkstack.c b/gtk/gtkstack.c
index 7764af3a8e..a769abd8eb 100644
--- a/gtk/gtkstack.c
+++ b/gtk/gtkstack.c
@@ -343,7 +343,7 @@ gtk_stack_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask =
-    gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+    gtk_widget_get_events (widget);
   attributes_mask = (GDK_WA_X | GDK_WA_Y) | GDK_WA_VISUAL;
 
   priv->view_window =
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index 697d63f53e..e9860d79e4 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -4602,7 +4602,7 @@ gtk_text_view_realize (GtkWidget *widget)
   attributes.height = allocation.height;
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
-  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK;
+  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK;
 
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 
@@ -9814,7 +9814,6 @@ text_window_realize (GtkTextWindow *win,
   attributes.width = win->allocation.width;
   attributes.height = win->allocation.height;
   attributes.event_mask = gtk_widget_get_events (win->widget)
-                          | GDK_EXPOSURE_MASK
                           | GDK_SCROLL_MASK
                           | GDK_SMOOTH_SCROLL_MASK
                           | GDK_KEY_PRESS_MASK
diff --git a/gtk/gtktoolitemgroup.c b/gtk/gtktoolitemgroup.c
index 785785d641..719ccff23d 100644
--- a/gtk/gtktoolitemgroup.c
+++ b/gtk/gtktoolitemgroup.c
@@ -1229,7 +1229,7 @@ gtk_tool_item_group_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask = gtk_widget_get_events (widget)
-                         | GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK
+                         | GDK_VISIBILITY_NOTIFY_MASK
                          | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK
                          | GDK_BUTTON_MOTION_MASK;
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
diff --git a/gtk/gtktoolpalette.c b/gtk/gtktoolpalette.c
index 70ca79f9c4..82e76375da 100644
--- a/gtk/gtktoolpalette.c
+++ b/gtk/gtktoolpalette.c
@@ -728,7 +728,7 @@ gtk_tool_palette_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
   attributes.event_mask = gtk_widget_get_events (widget)
-                         | GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK
+                         | GDK_VISIBILITY_NOTIFY_MASK
                          | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK
                          | GDK_BUTTON_MOTION_MASK
                          | GDK_SCROLL_MASK | GDK_SMOOTH_SCROLL_MASK
diff --git a/gtk/gtktreeview.c b/gtk/gtktreeview.c
index 852bc3c46f..3eec8e4ae4 100644
--- a/gtk/gtktreeview.c
+++ b/gtk/gtktreeview.c
@@ -2412,8 +2412,7 @@ gtk_tree_view_realize (GtkWidget *widget)
   attributes.y = gtk_tree_view_get_effective_header_height (tree_view);
   attributes.width = MAX (tree_view->priv->width, allocation.width);
   attributes.height = allocation.height;
-  attributes.event_mask = (GDK_EXPOSURE_MASK |
-                           GDK_SCROLL_MASK |
+  attributes.event_mask = (GDK_SCROLL_MASK |
                            GDK_SMOOTH_SCROLL_MASK |
                            GDK_POINTER_MOTION_MASK |
                            GDK_ENTER_NOTIFY_MASK |
@@ -2435,8 +2434,7 @@ gtk_tree_view_realize (GtkWidget *widget)
   attributes.y = 0;
   attributes.width = MAX (tree_view->priv->width, allocation.width);
   attributes.height = tree_view->priv->header_height;
-  attributes.event_mask = (GDK_EXPOSURE_MASK |
-                           GDK_SCROLL_MASK |
+  attributes.event_mask = (GDK_SCROLL_MASK |
                            GDK_ENTER_NOTIFY_MASK |
                            GDK_LEAVE_NOTIFY_MASK |
                            GDK_BUTTON_PRESS_MASK |
@@ -3951,7 +3949,7 @@ gtk_tree_view_motion_draw_column_motion_arrow (GtkTreeView *tree_view)
 	  width = attributes.width = drag_allocation.width;
 	  height = attributes.height = drag_allocation.height;
 	  attributes.visual = gdk_screen_get_rgba_visual (gtk_widget_get_screen (widget));
-	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK;
+	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
 	  attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 	  tree_view->priv->drag_highlight_window = gdk_window_new (tree_view->priv->header_window, &attributes, attributes_mask);
 	  gtk_widget_register_window (GTK_WIDGET (tree_view), tree_view->priv->drag_highlight_window);
@@ -3997,7 +3995,7 @@ gtk_tree_view_motion_draw_column_motion_arrow (GtkTreeView *tree_view)
 	  attributes.window_type = GDK_WINDOW_TEMP;
 	  attributes.wclass = GDK_INPUT_OUTPUT;
 	  attributes.visual = gtk_widget_get_visual (GTK_WIDGET (tree_view));
-	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK;
+	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
 	  attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
           attributes.x = x;
           attributes.y = y;
@@ -4078,7 +4076,7 @@ gtk_tree_view_motion_draw_column_motion_arrow (GtkTreeView *tree_view)
 	  attributes.window_type = GDK_WINDOW_TEMP;
 	  attributes.wclass = GDK_INPUT_OUTPUT;
 	  attributes.visual = gtk_widget_get_visual (GTK_WIDGET (tree_view));
-	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK;
+	  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
 	  attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
           attributes.x = x;
           attributes.y = y;
@@ -10041,7 +10039,7 @@ _gtk_tree_view_column_start_drag (GtkTreeView       *tree_view,
   attributes.width = button_allocation.width;
   attributes.height = button_allocation.height;
   attributes.visual = gtk_widget_get_visual (GTK_WIDGET (tree_view));
-  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK;
+  attributes.event_mask = GDK_VISIBILITY_NOTIFY_MASK | GDK_POINTER_MOTION_MASK;
   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
 
   tree_view->priv->drag_window = gdk_window_new (tree_view->priv->header_window,
diff --git a/gtk/gtkviewport.c b/gtk/gtkviewport.c
index 9b966052a6..f885292b15 100644
--- a/gtk/gtkviewport.c
+++ b/gtk/gtkviewport.c
@@ -747,7 +747,7 @@ gtk_viewport_realize (GtkWidget *widget)
   attributes.wclass = GDK_INPUT_OUTPUT;
   attributes.visual = gtk_widget_get_visual (widget);
 
-  event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
+  event_mask = gtk_widget_get_events (widget);
 
   attributes.event_mask = event_mask | GDK_SCROLL_MASK | GDK_TOUCH_MASK | GDK_SMOOTH_SCROLL_MASK;