diff --git a/gtk/tools/gtk-builder-tool-simplify.c b/gtk/tools/gtk-builder-tool-simplify.c
index 449a367aff..4287c1631a 100644
--- a/gtk/tools/gtk-builder-tool-simplify.c
+++ b/gtk/tools/gtk-builder-tool-simplify.c
@@ -721,15 +721,19 @@ maybe_rename_property (Element *element, MyParserData *data)
   struct _Prop {
     const char *class;
     const char *property;
+    GType type;
     PropKind kind;
     const char *new_name;
+    const char *alt_names[3];
   } props[] = {
-    { "GtkPopover", "modal", PROP_KIND_OBJECT, "autohide" },
+    { "GtkPopover", "modal", GTK_TYPE_POPOVER, PROP_KIND_OBJECT, "autohide", { NULL, NULL, NULL } },
+    { "GtkWidget", "expand", GTK_TYPE_WIDGET, PROP_KIND_OBJECT, "hexpand", { "vexpand",  NULL, NULL } },
+    { "GtkWidget", "margin", GTK_TYPE_WIDGET, PROP_KIND_OBJECT, "margin-left", { "margin-top",  "margin-right", "margin-bottom" } },
   };
-  char *canonical_name;
-  int i, k;
+  int i, k, l;
   PropKind kind;
   int prop_name_index = 0;
+  GParamSpec *pspec;
 
   kind = get_prop_kind (element);
 
@@ -748,22 +752,41 @@ maybe_rename_property (Element *element, MyParserData *data)
   if (property_name == NULL)
     return;
 
-  canonical_name = g_strdup (property_name);
-  g_strdelimit (canonical_name, "_", '-');
+  pspec = get_property_pspec (data, class_name, property_name, kind);
+  if (pspec == NULL)
+    return;
 
   for (k = 0; k < G_N_ELEMENTS (props); k++)
     {
-      if (strcmp (class_name, props[k].class) == 0 &&
-          strcmp (canonical_name, props[k].property) == 0 &&
+      if (pspec->owner_type == props[k].type &&
+          strcmp (pspec->name, props[k].property) == 0 &&
           kind == props[k].kind)
         {
           g_free (element->attribute_values[prop_name_index]);
           element->attribute_values[prop_name_index] = g_strdup (props[k].new_name);
+          for (l = 0; l < 3 && props[k].alt_names[l]; l++)
+            {
+              Element *elt;
+              GList *sibling;
+
+              elt = g_new0 (Element, 1);
+              elt->parent = element->parent;
+              elt->element_name = g_strdup (element->element_name);
+              elt->attribute_names = g_strdupv ((char **)element->attribute_names);
+              elt->attribute_values = g_strdupv ((char **)element->attribute_values);
+              elt->data = g_strdup (element->data);
+
+              g_free (elt->attribute_values[prop_name_index]);
+              elt->attribute_values[prop_name_index] = g_strdup (props[k].alt_names[l]);
+
+              sibling = g_list_find (element->parent->children, element);
+              element->parent->children = g_list_insert_before (element->parent->children,
+                                                                sibling,
+                                                                elt);
+            }
           break;
         }
     }
-
-  g_free (canonical_name);
 }
 
 static Element *