diff --git a/servo/components/script/dom/window.rs b/servo/components/script/dom/window.rs
index 5c1977626b2e..0294fb9f9885 100644
--- a/servo/components/script/dom/window.rs
+++ b/servo/components/script/dom/window.rs
@@ -540,7 +540,6 @@ pub trait WindowHelpers {
     fn content_box_query(self, content_box_request: TrustedNodeAddress) -> Rect<Au>;
     fn content_boxes_query(self, content_boxes_request: TrustedNodeAddress) -> Vec<Rect<Au>>;
     fn handle_reflow_complete_msg(self, reflow_id: u32);
-    fn handle_resize_inactive_msg(self, new_size: WindowSizeData);
     fn set_fragment_name(self, fragment: Option<String>);
     fn steal_fragment_name(self) -> Option<String>;
     fn set_window_size(self, size: WindowSizeData);
@@ -776,10 +775,6 @@ impl<'a> WindowHelpers for &'a Window {
         }
     }
 
-    fn handle_resize_inactive_msg(self, new_size: WindowSizeData) {
-        self.window_size.set(Some(new_size));
-    }
-
     fn init_browsing_context(self, doc: &Document, frame_element: Option<&Element>) {
         let mut browsing_context = self.browsing_context.borrow_mut();
         *browsing_context = Some(BrowsingContext::new(doc, frame_element));