diff --git a/components/style/gecko/wrapper.rs b/components/style/gecko/wrapper.rs
index da989e5a74a..f76c0c5fda6 100644
--- a/components/style/gecko/wrapper.rs
+++ b/components/style/gecko/wrapper.rs
@@ -300,7 +300,10 @@ impl<'ln> GeckoNode<'ln> {
     fn flattened_tree_parent_is_parent(&self) -> bool {
         use crate::gecko_bindings::structs::*;
         let flags = self.flags();
-        if flags & (NODE_MAY_BE_IN_BINDING_MNGR as u32 | NODE_IS_IN_SHADOW_TREE as u32) != 0 {
+
+        // FIXME(emilio): The shadow tree condition seems it shouldn't be needed
+        // anymore, if we check for slots.
+        if self.is_in_shadow_tree() {
             return false;
         }