diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 3304e23cb64..ed04d2e562c 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -111,6 +111,7 @@ use std::cell::Cell;
 use std::default::Default;
 use std::fmt;
 use std::mem;
+use std::ops::Deref;
 use std::rc::Rc;
 use std::str::FromStr;
 use style::applicable_declarations::ApplicableDeclarationBlock;
@@ -3218,15 +3219,11 @@ impl<'a> SelectorsElement for DomRoot<Element> {
             Element::namespace(self) == Element::namespace(other)
     }
 
-    fn match_non_ts_pseudo_class<F>(
+    fn match_non_ts_pseudo_class(
         &self,
         pseudo_class: &NonTSPseudoClass,
         _: &mut MatchingContext<Self::Impl>,
-        _: &mut F,
-    ) -> bool
-    where
-        F: FnMut(&Self, ElementSelectorFlags),
-    {
+    ) -> bool {
         match *pseudo_class {
             // https://github.com/servo/servo/issues/8718
             NonTSPseudoClass::Link | NonTSPseudoClass::AnyLink => self.is_link(),
@@ -3307,6 +3304,15 @@ impl<'a> SelectorsElement for DomRoot<Element> {
     fn is_html_slot_element(&self) -> bool {
         self.is_html_element() && self.local_name() == &local_name!("slot")
     }
+
+    fn set_selector_flags(&self, flags: ElementSelectorFlags) {
+        #[allow(unsafe_code)]
+        unsafe {
+            Dom::from_ref(self.deref())
+                .to_layout()
+                .insert_selector_flags(flags);
+        }
+    }
 }
 
 impl Element {
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index a4913faa683..7e3367b9b2a 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -79,7 +79,9 @@ use script_layout_interface::{HTMLCanvasData, HTMLMediaData, LayoutElementType,
 use script_layout_interface::{SVGSVGData, StyleAndOpaqueLayoutData, TrustedNodeAddress};
 use script_traits::DocumentActivity;
 use script_traits::UntrustedNodeAddress;
-use selectors::matching::{matches_selector_list, MatchingContext, MatchingMode};
+use selectors::matching::{
+    matches_selector_list, MatchingContext, MatchingMode, NeedsSelectorFlags,
+};
 use selectors::parser::SelectorList;
 use servo_arc::Arc;
 use servo_url::ServoUrl;
@@ -473,6 +475,7 @@ impl<'a> Iterator for QuerySelectorIterator {
                     None,
                     None,
                     node.owner_doc().quirks_mode(),
+                    NeedsSelectorFlags::No,
                 );
                 if let Some(element) = DomRoot::downcast(node) {
                     if matches_selector_list(selectors, &element, &mut ctx) {
@@ -956,8 +959,13 @@ impl Node {
             // Step 3.
             Ok(selectors) => {
                 // FIXME(bholley): Consider an nth-index cache here.
-                let mut ctx =
-                    MatchingContext::new(MatchingMode::Normal, None, None, doc.quirks_mode());
+                let mut ctx = MatchingContext::new(
+                    MatchingMode::Normal,
+                    None,
+                    None,
+                    doc.quirks_mode(),
+                    NeedsSelectorFlags::No,
+                );
                 Ok(self
                     .traverse_preorder(ShadowIncluding::No)
                     .filter_map(DomRoot::downcast)
diff --git a/components/script/layout_dom/element.rs b/components/script/layout_dom/element.rs
index 82a485c3357..22325ab4f92 100644
--- a/components/script/layout_dom/element.rs
+++ b/components/script/layout_dom/element.rs
@@ -358,10 +358,6 @@ impl<'dom, LayoutDataType: LayoutDataTrait> style::dom::TElement
         false
     }
 
-    fn set_selector_flags(&self, flags: ElementSelectorFlags) {
-        self.element.insert_selector_flags(flags);
-    }
-
     fn has_animations(&self, context: &SharedStyleContext) -> bool {
         // This is not used for pseudo elements currently so we can pass None.
         return self.has_css_animations(context, /* pseudo_element = */ None) ||
@@ -569,15 +565,11 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
         false
     }
 
-    fn match_non_ts_pseudo_class<F>(
+    fn match_non_ts_pseudo_class(
         &self,
         pseudo_class: &NonTSPseudoClass,
         _: &mut MatchingContext<Self::Impl>,
-        _: &mut F,
-    ) -> bool
-    where
-        F: FnMut(&Self, ElementSelectorFlags),
-    {
+    ) -> bool {
         match *pseudo_class {
             // https://github.com/servo/servo/issues/8718
             NonTSPseudoClass::Link | NonTSPseudoClass::AnyLink => self.is_link(),
@@ -666,6 +658,10 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
     fn is_html_element_in_html_document(&self) -> bool {
         self.element.is_html_element() && self.as_node().owner_doc().is_html_document()
     }
+
+    fn set_selector_flags(&self, flags: ElementSelectorFlags) {
+        self.element.insert_selector_flags(flags);
+    }
 }
 
 /// A wrapper around elements that ensures layout can only
@@ -854,15 +850,11 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
         }
     }
 
-    fn match_non_ts_pseudo_class<F>(
+    fn match_non_ts_pseudo_class(
         &self,
         _: &NonTSPseudoClass,
         _: &mut MatchingContext<Self::Impl>,
-        _: &mut F,
-    ) -> bool
-    where
-        F: FnMut(&Self, ElementSelectorFlags),
-    {
+    ) -> bool {
         // NB: This could maybe be implemented
         warn!("ServoThreadSafeLayoutElement::match_non_ts_pseudo_class called");
         false
@@ -903,6 +895,10 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
         warn!("ServoThreadSafeLayoutElement::is_root called");
         false
     }
+
+    fn set_selector_flags(&self, flags: ElementSelectorFlags) {
+        self.element.element.insert_selector_flags(flags);
+    }
 }
 
 impl<'dom, LayoutDataType: LayoutDataTrait> GetStyleAndOpaqueLayoutData<'dom>