diff --git a/gtk/gtklayoutmanager.c b/gtk/gtklayoutmanager.c
index 6467b8ee5a..47ced92b07 100644
--- a/gtk/gtklayoutmanager.c
+++ b/gtk/gtklayoutmanager.c
@@ -122,7 +122,12 @@ gtk_layout_manager_real_get_request_mode (GtkLayoutManager *manager,
        child != NULL;
        child = _gtk_widget_get_next_sibling (child))
     {
-      GtkSizeRequestMode res = gtk_widget_get_request_mode (child);
+      GtkSizeRequestMode res;
+
+      if (!gtk_widget_should_layout (child))
+        continue;
+
+      res = gtk_widget_get_request_mode (child);
 
       switch (res)
         {
@@ -143,8 +148,8 @@ gtk_layout_manager_real_get_request_mode (GtkLayoutManager *manager,
  if (hfw == 0 && wfh == 0)
    return GTK_SIZE_REQUEST_CONSTANT_SIZE;
 
- return hfw > wfh ? GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH
-                  : GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT;
+ return hfw >= wfh ? GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH
+                   : GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT;
 }
 
 static void
diff --git a/gtk/gtkstack.c b/gtk/gtkstack.c
index 001bb26d65..a19f9cea7b 100644
--- a/gtk/gtkstack.c
+++ b/gtk/gtkstack.c
@@ -2328,9 +2328,30 @@ gtk_stack_compute_expand (GtkWidget *widget,
 static GtkSizeRequestMode
 gtk_stack_get_request_mode (GtkWidget *widget)
 {
+  GtkStack *stack = GTK_STACK (widget);
+  GtkStackPrivate *priv = gtk_stack_get_instance_private (stack);
   GtkWidget *w;
   int wfh = 0, hfw = 0;
 
+  if (!priv->homogeneous[GTK_ORIENTATION_VERTICAL] &&
+      !priv->homogeneous[GTK_ORIENTATION_HORIZONTAL])
+    {
+      GtkSizeRequestMode lv_mode;
+
+      /* Only the visible child, and perhaps the last visible child
+       * during a transition, matter.  Attempt to return constant-size
+       * when we can.  */
+      if (priv->last_visible_child)
+        lv_mode = gtk_widget_get_request_mode (priv->last_visible_child->widget);
+      else
+        lv_mode = GTK_SIZE_REQUEST_CONSTANT_SIZE;
+
+      if (lv_mode == GTK_SIZE_REQUEST_CONSTANT_SIZE && priv->visible_child)
+        return gtk_widget_get_request_mode (priv->visible_child->widget);
+      else
+        return lv_mode;
+    }
+
   for (w = gtk_widget_get_first_child (widget);
        w != NULL;
        w = gtk_widget_get_next_sibling (w))