diff --git a/components/script/dom/cssmediarule.rs b/components/script/dom/cssmediarule.rs
index 50456680193..808c988add8 100644
--- a/components/script/dom/cssmediarule.rs
+++ b/components/script/dom/cssmediarule.rs
@@ -4,7 +4,7 @@
 
 use dom_struct::dom_struct;
 use servo_arc::Arc;
-use style::shared_lock::{Locked, ToCssWithGuard};
+use style::shared_lock::ToCssWithGuard;
 use style::stylesheets::MediaRule;
 use style_traits::ToCss;
 
@@ -23,17 +23,13 @@ pub struct CSSMediaRule {
     cssconditionrule: CSSConditionRule,
     #[ignore_malloc_size_of = "Arc"]
     #[no_trace]
-    mediarule: Arc<Locked<MediaRule>>,
+    mediarule: Arc<MediaRule>,
     medialist: MutNullableDom<MediaList>,
 }
 
 impl CSSMediaRule {
-    fn new_inherited(
-        parent_stylesheet: &CSSStyleSheet,
-        mediarule: Arc<Locked<MediaRule>>,
-    ) -> CSSMediaRule {
-        let guard = parent_stylesheet.shared_lock().read();
-        let list = mediarule.read_with(&guard).rules.clone();
+    fn new_inherited(parent_stylesheet: &CSSStyleSheet, mediarule: Arc<MediaRule>) -> CSSMediaRule {
+        let list = mediarule.rules.clone();
         CSSMediaRule {
             cssconditionrule: CSSConditionRule::new_inherited(parent_stylesheet, list),
             mediarule: mediarule,
@@ -45,7 +41,7 @@ impl CSSMediaRule {
     pub fn new(
         window: &Window,
         parent_stylesheet: &CSSStyleSheet,
-        mediarule: Arc<Locked<MediaRule>>,
+        mediarule: Arc<MediaRule>,
     ) -> DomRoot<CSSMediaRule> {
         reflect_dom_object(
             Box::new(CSSMediaRule::new_inherited(parent_stylesheet, mediarule)),
@@ -55,11 +51,10 @@ impl CSSMediaRule {
 
     fn medialist(&self) -> DomRoot<MediaList> {
         self.medialist.or_init(|| {
-            let guard = self.cssconditionrule.shared_lock().read();
             MediaList::new(
                 self.global().as_window(),
                 self.cssconditionrule.parent_stylesheet(),
-                self.mediarule.read_with(&guard).media_queries.clone(),
+                self.mediarule.media_queries.clone(),
             )
         })
     }
@@ -67,8 +62,7 @@ impl CSSMediaRule {
     /// <https://drafts.csswg.org/css-conditional-3/#the-cssmediarule-interface>
     pub fn get_condition_text(&self) -> DOMString {
         let guard = self.cssconditionrule.shared_lock().read();
-        let rule = self.mediarule.read_with(&guard);
-        let list = rule.media_queries.read_with(&guard);
+        let list = self.mediarule.media_queries.read_with(&guard);
         list.to_css_string().into()
     }
 }
@@ -81,10 +75,7 @@ impl SpecificCSSRule for CSSMediaRule {
 
     fn get_css(&self) -> DOMString {
         let guard = self.cssconditionrule.shared_lock().read();
-        self.mediarule
-            .read_with(&guard)
-            .to_css_string(&guard)
-            .into()
+        self.mediarule.to_css_string(&guard).into()
     }
 }
 
diff --git a/components/script/dom/cssnamespacerule.rs b/components/script/dom/cssnamespacerule.rs
index 173adc54a1a..cd648e1338c 100644
--- a/components/script/dom/cssnamespacerule.rs
+++ b/components/script/dom/cssnamespacerule.rs
@@ -4,7 +4,7 @@
 
 use dom_struct::dom_struct;
 use servo_arc::Arc;
-use style::shared_lock::{Locked, ToCssWithGuard};
+use style::shared_lock::ToCssWithGuard;
 use style::stylesheets::NamespaceRule;
 
 use crate::dom::bindings::codegen::Bindings::CSSNamespaceRuleBinding::CSSNamespaceRuleMethods;
@@ -20,13 +20,13 @@ pub struct CSSNamespaceRule {
     cssrule: CSSRule,
     #[ignore_malloc_size_of = "Arc"]
     #[no_trace]
-    namespacerule: Arc<Locked<NamespaceRule>>,
+    namespacerule: Arc<NamespaceRule>,
 }
 
 impl CSSNamespaceRule {
     fn new_inherited(
         parent_stylesheet: &CSSStyleSheet,
-        namespacerule: Arc<Locked<NamespaceRule>>,
+        namespacerule: Arc<NamespaceRule>,
     ) -> CSSNamespaceRule {
         CSSNamespaceRule {
             cssrule: CSSRule::new_inherited(parent_stylesheet),
@@ -38,7 +38,7 @@ impl CSSNamespaceRule {
     pub fn new(
         window: &Window,
         parent_stylesheet: &CSSStyleSheet,
-        namespacerule: Arc<Locked<NamespaceRule>>,
+        namespacerule: Arc<NamespaceRule>,
     ) -> DomRoot<CSSNamespaceRule> {
         reflect_dom_object(
             Box::new(CSSNamespaceRule::new_inherited(
@@ -53,9 +53,7 @@ impl CSSNamespaceRule {
 impl CSSNamespaceRuleMethods for CSSNamespaceRule {
     // https://drafts.csswg.org/cssom/#dom-cssnamespacerule-prefix
     fn Prefix(&self) -> DOMString {
-        let guard = self.cssrule.shared_lock().read();
         self.namespacerule
-            .read_with(&guard)
             .prefix
             .as_ref()
             .map(|s| s.to_string().into())
@@ -64,8 +62,7 @@ impl CSSNamespaceRuleMethods for CSSNamespaceRule {
 
     // https://drafts.csswg.org/cssom/#dom-cssnamespacerule-namespaceuri
     fn NamespaceURI(&self) -> DOMString {
-        let guard = self.cssrule.shared_lock().read();
-        (**self.namespacerule.read_with(&guard).url).into()
+        (**self.namespacerule.url).into()
     }
 }
 
@@ -77,9 +74,6 @@ impl SpecificCSSRule for CSSNamespaceRule {
 
     fn get_css(&self) -> DOMString {
         let guard = self.cssrule.shared_lock().read();
-        self.namespacerule
-            .read_with(&guard)
-            .to_css_string(&guard)
-            .into()
+        self.namespacerule.to_css_string(&guard).into()
     }
 }
diff --git a/components/script/dom/csssupportsrule.rs b/components/script/dom/csssupportsrule.rs
index 3c9b4e48647..53714358b39 100644
--- a/components/script/dom/csssupportsrule.rs
+++ b/components/script/dom/csssupportsrule.rs
@@ -4,7 +4,7 @@
 
 use dom_struct::dom_struct;
 use servo_arc::Arc;
-use style::shared_lock::{Locked, ToCssWithGuard};
+use style::shared_lock::ToCssWithGuard;
 use style::stylesheets::SupportsRule;
 use style_traits::ToCss;
 
@@ -21,16 +21,15 @@ pub struct CSSSupportsRule {
     cssconditionrule: CSSConditionRule,
     #[ignore_malloc_size_of = "Arc"]
     #[no_trace]
-    supportsrule: Arc<Locked<SupportsRule>>,
+    supportsrule: Arc<SupportsRule>,
 }
 
 impl CSSSupportsRule {
     fn new_inherited(
         parent_stylesheet: &CSSStyleSheet,
-        supportsrule: Arc<Locked<SupportsRule>>,
+        supportsrule: Arc<SupportsRule>,
     ) -> CSSSupportsRule {
-        let guard = parent_stylesheet.shared_lock().read();
-        let list = supportsrule.read_with(&guard).rules.clone();
+        let list = supportsrule.rules.clone();
         CSSSupportsRule {
             cssconditionrule: CSSConditionRule::new_inherited(parent_stylesheet, list),
             supportsrule: supportsrule,
@@ -41,7 +40,7 @@ impl CSSSupportsRule {
     pub fn new(
         window: &Window,
         parent_stylesheet: &CSSStyleSheet,
-        supportsrule: Arc<Locked<SupportsRule>>,
+        supportsrule: Arc<SupportsRule>,
     ) -> DomRoot<CSSSupportsRule> {
         reflect_dom_object(
             Box::new(CSSSupportsRule::new_inherited(
@@ -54,9 +53,7 @@ impl CSSSupportsRule {
 
     /// <https://drafts.csswg.org/css-conditional-3/#the-csssupportsrule-interface>
     pub fn get_condition_text(&self) -> DOMString {
-        let guard = self.cssconditionrule.shared_lock().read();
-        let rule = self.supportsrule.read_with(&guard);
-        rule.condition.to_css_string().into()
+        self.supportsrule.condition.to_css_string().into()
     }
 }
 
@@ -68,9 +65,6 @@ impl SpecificCSSRule for CSSSupportsRule {
 
     fn get_css(&self) -> DOMString {
         let guard = self.cssconditionrule.shared_lock().read();
-        self.supportsrule
-            .read_with(&guard)
-            .to_css_string(&guard)
-            .into()
+        self.supportsrule.to_css_string(&guard).into()
     }
 }
diff --git a/components/style/stylesheets/stylesheet.rs b/components/style/stylesheets/stylesheet.rs
index 2f0cbdcdfbb..3994e5cab68 100644
--- a/components/style/stylesheets/stylesheet.rs
+++ b/components/style/stylesheets/stylesheet.rs
@@ -209,6 +209,26 @@ pub struct Stylesheet {
 }
 
 macro_rules! rule_filter {
+    ($( $method: ident($variant:ident => $rule_type: ident), )+) => {
+        $(
+            #[allow(missing_docs)]
+            fn $method<F>(&self, device: &Device, guard: &SharedRwLockReadGuard, mut f: F)
+                where F: FnMut(&crate::stylesheets::$rule_type),
+            {
+                use crate::stylesheets::CssRule;
+
+                for rule in self.effective_rules(device, guard) {
+                    if let CssRule::$variant(ref lock) = *rule {
+                        let rule = lock.read_with(guard);
+                        f(&rule)
+                    }
+                }
+            }
+        )+
+    }
+}
+
+macro_rules! rule_filter_for_non_locked {
     ($( $method: ident($variant:ident => $rule_type: ident), )+) => {
         $(
             #[allow(missing_docs)]
@@ -283,6 +303,9 @@ pub trait StylesheetInDocument: ::std::fmt::Debug {
 
     rule_filter! {
         effective_font_face_rules(FontFace => FontFaceRule),
+    }
+
+    rule_filter_for_non_locked! {
         effective_viewport_rules(Viewport => ViewportRule),
     }
 }