diff --git a/gtk/gtkcssstyleproperty.c b/gtk/gtkcssstyleproperty.c
index 7bb1e688e2..9327921d5a 100644
--- a/gtk/gtkcssstyleproperty.c
+++ b/gtk/gtkcssstyleproperty.c
@@ -38,6 +38,7 @@
 enum {
   PROP_0,
   PROP_ANIMATED,
+  PROP_AFFECTS_SIZE,
   PROP_ID,
   PROP_INHERIT,
   PROP_INITIAL
@@ -70,6 +71,9 @@ gtk_css_style_property_set_property (GObject      *object,
     case PROP_ANIMATED:
       property->animated = g_value_get_boolean (value);
       break;
+    case PROP_AFFECTS_SIZE:
+      property->affects_size = g_value_get_boolean (value);
+      break;
     case PROP_INHERIT:
       property->inherit = g_value_get_boolean (value);
       break;
@@ -96,6 +100,9 @@ gtk_css_style_property_get_property (GObject    *object,
     case PROP_ANIMATED:
       g_value_set_boolean (value, property->animated);
       break;
+    case PROP_AFFECTS_SIZE:
+      g_value_set_boolean (value, property->affects_size);
+      break;
     case PROP_ID:
       g_value_set_boolean (value, property->id);
       break;
@@ -251,6 +258,13 @@ _gtk_css_style_property_class_init (GtkCssStylePropertyClass *klass)
                                                          P_("Set if the value can be animated"),
                                                          FALSE,
                                                          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
+  g_object_class_install_property (object_class,
+                                   PROP_AFFECTS_SIZE,
+                                   g_param_spec_boolean ("affects-size",
+                                                         P_("Affects size"),
+                                                         P_("Set if the value affects the sizing of elements"),
+                                                         TRUE,
+                                                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
   g_object_class_install_property (object_class,
                                    PROP_ID,
                                    g_param_spec_uint ("id",
@@ -381,6 +395,23 @@ _gtk_css_style_property_is_animated (GtkCssStyleProperty *property)
   return property->animated;
 }
 
+/**
+ * _gtk_css_style_property_affects_size:
+ * @property: the property
+ *
+ * Queries if the given @property affects the size of elements. This is
+ * used for optimizations inside GTK, where a gtk_widget_queue_resize()
+ * can be avoided if the property does not affect size.
+ *
+ * Returns: %TRUE if the property affects sizing of elements.
+ **/
+gboolean
+_gtk_css_style_property_affects_size (GtkCssStyleProperty *property)
+{
+  g_return_val_if_fail (GTK_IS_CSS_STYLE_PROPERTY (property), FALSE);
+
+  return property->affects_size;
+}
 /**
  * _gtk_css_style_property_get_id:
  * @property: the property
diff --git a/gtk/gtkcssstylepropertyprivate.h b/gtk/gtkcssstylepropertyprivate.h
index b04b2679a9..34411e0693 100644
--- a/gtk/gtkcssstylepropertyprivate.h
+++ b/gtk/gtkcssstylepropertyprivate.h
@@ -49,6 +49,7 @@ struct _GtkCssStyleProperty
   guint id;
   guint inherit :1;
   guint animated :1;
+  guint affects_size :1;
 
   GtkCssStylePropertyParseFunc parse_value;
   GtkCssStylePropertyQueryFunc query_value;
@@ -71,6 +72,7 @@ GtkCssStyleProperty *   _gtk_css_style_property_lookup_by_id    (guint
 
 gboolean                _gtk_css_style_property_is_inherit      (GtkCssStyleProperty    *property);
 gboolean                _gtk_css_style_property_is_animated     (GtkCssStyleProperty    *property);
+gboolean                _gtk_css_style_property_affects_size    (GtkCssStyleProperty    *property);
 guint                   _gtk_css_style_property_get_id          (GtkCssStyleProperty    *property);
 GtkCssValue  *          _gtk_css_style_property_get_initial_value
                                                                 (GtkCssStyleProperty    *property);