diff --git a/src/st/st-theme-node-private.h b/src/st/st-theme-node-private.h
index 02eb95e52..b8028925e 100644
--- a/src/st/st-theme-node-private.h
+++ b/src/st/st-theme-node-private.h
@@ -105,7 +105,7 @@ struct _StThemeNode {
   int box_shadow_min_width;
   int box_shadow_min_height;
 
-  guint stylesheets_changed_id;
+  gulong stylesheets_changed_id;
 
   CoglTexture *border_slices_texture;
   CoglPipeline *border_slices_pipeline;
diff --git a/src/st/st-theme-node.c b/src/st/st-theme-node.c
index b471ad72b..31b27583c 100644
--- a/src/st/st-theme-node.c
+++ b/src/st/st-theme-node.c
@@ -75,6 +75,10 @@ maybe_free_properties (StThemeNode *node)
       cr_declaration_destroy (node->inline_properties);
       node->inline_properties = NULL;
     }
+
+  g_clear_signal_handler (&node->stylesheets_changed_id, node->theme);
+
+  node->properties_computed = FALSE;
 }
 
 static void
@@ -472,6 +476,16 @@ ensure_properties (StThemeNode *node)
           node->n_properties = properties->len;
           node->properties = (CRDeclaration **)g_ptr_array_free (properties, FALSE);
         }
+
+      if (!node->stylesheets_changed_id)
+        {
+          node->stylesheets_changed_id =
+            g_signal_connect_object (node->theme,
+                                     "custom-stylesheets-changed",
+                                     G_CALLBACK (maybe_free_properties),
+                                     G_OBJECT (node),
+                                     G_CONNECT_SWAPPED);
+        }
     }
 }