diff --git a/components/style/gecko/data.rs b/components/style/gecko/data.rs
index 2e1e17a2ebc..64252c79afc 100644
--- a/components/style/gecko/data.rs
+++ b/components/style/gecko/data.rs
@@ -108,18 +108,26 @@ impl PerDocumentStyleDataImpl {
         let author_style_disabled = self.stylesheets.author_style_disabled();
         let mut stylesheets = Vec::<Arc<Stylesheet>>::new();
         self.stylesheets.flush(&mut stylesheets);
-        stylist.update(stylesheets.as_slice(),
-                       &StylesheetGuards::same(guard),
-                       /* ua_sheets = */ None,
-                       /* stylesheets_changed = */ true,
-                       author_style_disabled,
-                       &mut extra_data);
+        stylist.clear();
+        stylist.rebuild(stylesheets.as_slice(),
+                        &StylesheetGuards::same(guard),
+                        /* ua_sheets = */ None,
+                        /* stylesheets_changed = */ true,
+                        author_style_disabled,
+                        &mut extra_data);
     }
 
     /// Get the default computed values for this document.
     pub fn default_computed_values(&self) -> &Arc<ComputedValues> {
         self.stylist.device.default_computed_values_arc()
     }
+
+    /// Clear the stylist.  This will be a no-op if the stylist is
+    /// already cleared; the stylist handles that.
+    pub fn clear_stylist(&mut self) {
+        let mut stylist = Arc::get_mut(&mut self.stylist).unwrap();
+        stylist.clear();
+    }
 }
 
 unsafe impl HasFFI for PerDocumentStyleData {
diff --git a/components/style/gecko/generated/bindings.rs b/components/style/gecko/generated/bindings.rs
index eddc0d90c76..ddb888a678c 100644
--- a/components/style/gecko/generated/bindings.rs
+++ b/components/style/gecko/generated/bindings.rs
@@ -1626,16 +1626,16 @@ extern "C" {
 extern "C" {
     pub fn Servo_StyleSet_AppendStyleSheet(set: RawServoStyleSetBorrowed,
                                            sheet: RawServoStyleSheetBorrowed,
-                                           unique_id: u32, flush: bool);
+                                           unique_id: u32);
 }
 extern "C" {
     pub fn Servo_StyleSet_PrependStyleSheet(set: RawServoStyleSetBorrowed,
                                             sheet: RawServoStyleSheetBorrowed,
-                                            unique_id: u32, flush: bool);
+                                            unique_id: u32);
 }
 extern "C" {
     pub fn Servo_StyleSet_RemoveStyleSheet(set: RawServoStyleSetBorrowed,
-                                           unique_id: u32, flush: bool);
+                                           unique_id: u32);
 }
 extern "C" {
     pub fn Servo_StyleSet_InsertStyleSheetBefore(set:
@@ -1643,8 +1643,7 @@ extern "C" {
                                                  sheet:
                                                      RawServoStyleSheetBorrowed,
                                                  unique_id: u32,
-                                                 before_unique_id: u32,
-                                                 flush: bool);
+                                                 before_unique_id: u32);
 }
 extern "C" {
     pub fn Servo_StyleSet_FlushStyleSheets(set: RawServoStyleSetBorrowed);
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 3de322d9d98..6cb6dae48a5 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -595,60 +595,40 @@ pub extern "C" fn Servo_StyleSheet_ClearAndUpdate(stylesheet: RawServoStyleSheet
 #[no_mangle]
 pub extern "C" fn Servo_StyleSet_AppendStyleSheet(raw_data: RawServoStyleSetBorrowed,
                                                   raw_sheet: RawServoStyleSheetBorrowed,
-                                                  unique_id: u32,
-                                                  flush: bool) {
-    let global_style_data = &*GLOBAL_STYLE_DATA;
-    let guard = global_style_data.shared_lock.read();
+                                                  unique_id: u32) {
     let mut data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     let sheet = HasArcFFI::as_arc(&raw_sheet);
     data.stylesheets.append_stylesheet(sheet, unique_id);
-    if flush {
-        data.flush_stylesheets(&guard);
-    }
+    data.clear_stylist();
 }
 
 #[no_mangle]
 pub extern "C" fn Servo_StyleSet_PrependStyleSheet(raw_data: RawServoStyleSetBorrowed,
                                                    raw_sheet: RawServoStyleSheetBorrowed,
-                                                   unique_id: u32,
-                                                   flush: bool) {
-    let global_style_data = &*GLOBAL_STYLE_DATA;
-    let guard = global_style_data.shared_lock.read();
+                                                   unique_id: u32) {
     let mut data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     let sheet = HasArcFFI::as_arc(&raw_sheet);
     data.stylesheets.prepend_stylesheet(sheet, unique_id);
-    if flush {
-        data.flush_stylesheets(&guard);
-    }
+    data.clear_stylist();
 }
 
 #[no_mangle]
 pub extern "C" fn Servo_StyleSet_InsertStyleSheetBefore(raw_data: RawServoStyleSetBorrowed,
                                                         raw_sheet: RawServoStyleSheetBorrowed,
                                                         unique_id: u32,
-                                                        before_unique_id: u32,
-                                                        flush: bool) {
-    let global_style_data = &*GLOBAL_STYLE_DATA;
-    let guard = global_style_data.shared_lock.read();
+                                                        before_unique_id: u32) {
     let mut data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     let sheet = HasArcFFI::as_arc(&raw_sheet);
     data.stylesheets.insert_stylesheet_before(sheet, unique_id, before_unique_id);
-    if flush {
-        data.flush_stylesheets(&guard);
-    }
+    data.clear_stylist();
 }
 
 #[no_mangle]
 pub extern "C" fn Servo_StyleSet_RemoveStyleSheet(raw_data: RawServoStyleSetBorrowed,
-                                                  unique_id: u32,
-                                                  flush: bool) {
-    let global_style_data = &*GLOBAL_STYLE_DATA;
-    let guard = global_style_data.shared_lock.read();
+                                                  unique_id: u32) {
     let mut data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     data.stylesheets.remove_stylesheet(unique_id);
-    if flush {
-        data.flush_stylesheets(&guard);
-    }
+    data.clear_stylist();
 }
 
 #[no_mangle]
@@ -665,6 +645,7 @@ pub extern "C" fn Servo_StyleSet_NoteStyleSheetsChanged(raw_data: RawServoStyleS
     let mut data = PerDocumentStyleData::from_ffi(raw_data).borrow_mut();
     data.stylesheets.force_dirty();
     data.stylesheets.set_author_style_disabled(author_style_disabled);
+    data.clear_stylist();
 }
 
 #[no_mangle]