diff --git a/components/layout_thread/dom_wrapper.rs b/components/layout_thread/dom_wrapper.rs
index 1aa9488c327..0558d648eb8 100644
--- a/components/layout_thread/dom_wrapper.rs
+++ b/components/layout_thread/dom_wrapper.rs
@@ -313,6 +313,10 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
         self.node.downcast().map(ServoShadowRoot::from_layout_js)
     }
 
+    fn is_in_document(&self) -> bool {
+        unsafe { self.node.get_flag(NodeFlags::IS_IN_DOC) }
+    }
+
     fn is_connected(&self) -> bool {
         unsafe { self.node.get_flag(NodeFlags::IS_CONNECTED) }
     }
@@ -555,7 +559,7 @@ impl<'le> TElement for ServoLayoutElement<'le> {
     }
 
     unsafe fn set_dirty_descendants(&self) {
-        debug_assert!(self.as_node().is_connected());
+        debug_assert!(self.as_node().is_in_document());
         self.as_node()
             .node
             .set_flag(NodeFlags::HAS_DIRTY_DESCENDANTS, true)
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index c58313f6ee0..0d25b535593 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -644,7 +644,7 @@ impl Document {
     }
 
     pub fn content_and_heritage_changed(&self, node: &Node) {
-        if node.is_connected() {
+        if node.is_in_doc() {
             node.note_dirty_descendants();
         }
 
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 79d838c5292..a93389638fe 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -568,7 +568,7 @@ impl Node {
 
     // FIXME(emilio): This and the function below should move to Element.
     pub fn note_dirty_descendants(&self) {
-        debug_assert!(self.is_connected());
+        debug_assert!(self.is_in_doc());
 
         for ancestor in self.shadow_including_inclusive_ancestors() {
             if ancestor.get_flag(NodeFlags::HAS_DIRTY_DESCENDANTS) {
diff --git a/components/style/dom.rs b/components/style/dom.rs
index d282ceeafad..541ef4dbcdc 100644
--- a/components/style/dom.rs
+++ b/components/style/dom.rs
@@ -185,6 +185,9 @@ pub trait TNode: Sized + Copy + Clone + Debug + NodeInfo + PartialEq {
         DomChildren(self.first_child())
     }
 
+    /// Returns whether the node is attached to a document.
+    fn is_in_document(&self) -> bool;
+
     /// Returns whether the node is connected.
     fn is_connected(&self) -> bool;
 
diff --git a/components/style/gecko/wrapper.rs b/components/style/gecko/wrapper.rs
index 0fa354fb139..e8e5078c53a 100644
--- a/components/style/gecko/wrapper.rs
+++ b/components/style/gecko/wrapper.rs
@@ -421,6 +421,11 @@ impl<'ln> TNode for GeckoNode<'ln> {
         self.get_bool_flag(nsINode_BooleanFlag::IsInDocument)
     }
 
+    #[inline]
+    fn is_connected(&self) -> bool {
+        self.get_bool_flag(nsINode_BooleanFlag::IsConnected)
+    }
+
     fn traversal_parent(&self) -> Option<GeckoElement<'ln>> {
         self.flattened_tree_parent().and_then(|n| n.as_element())
     }