diff --git a/components/style/gecko/arc_types.rs b/components/style/gecko/arc_types.rs
index 707266d2bec..8088482d3cf 100644
--- a/components/style/gecko/arc_types.rs
+++ b/components/style/gecko/arc_types.rs
@@ -114,9 +114,8 @@ impl_locked_arc_ffi!(
     Servo_PageRule_AddRef,
     Servo_PageRule_Release
 );
-impl_locked_arc_ffi!(
+impl_simple_arc_ffi!(
     PropertyRule,
-    LockedPropertyRule,
     Servo_PropertyRule_AddRef,
     Servo_PropertyRule_Release
 );
diff --git a/components/style/stylesheets/mod.rs b/components/style/stylesheets/mod.rs
index 5230ab63e94..6d1a8e775b4 100644
--- a/components/style/stylesheets/mod.rs
+++ b/components/style/stylesheets/mod.rs
@@ -263,7 +263,7 @@ pub enum CssRule {
     Keyframes(Arc<Locked<KeyframesRule>>),
     Supports(Arc<Locked<SupportsRule>>),
     Page(Arc<Locked<PageRule>>),
-    Property(Arc<Locked<PropertyRule>>),
+    Property(Arc<PropertyRule>),
     Document(Arc<Locked<DocumentRule>>),
     LayerBlock(Arc<Locked<LayerBlockRule>>),
     LayerStatement(Arc<Locked<LayerStatementRule>>),
@@ -309,9 +309,7 @@ impl CssRule {
                 lock.unconditional_shallow_size_of(ops) + lock.read_with(guard).size_of(guard, ops)
             },
 
-            CssRule::Property(ref lock) => {
-                lock.unconditional_shallow_size_of(ops) + lock.read_with(guard).size_of(guard, ops)
-            },
+            CssRule::Property(ref rule) => rule.size_of(guard, ops),
 
             CssRule::Document(ref lock) => {
                 lock.unconditional_shallow_size_of(ops) + lock.read_with(guard).size_of(guard, ops)
@@ -598,7 +596,7 @@ impl ToCssWithGuard for CssRule {
             CssRule::Media(ref lock) => lock.read_with(guard).to_css(guard, dest),
             CssRule::Supports(ref lock) => lock.read_with(guard).to_css(guard, dest),
             CssRule::Page(ref lock) => lock.read_with(guard).to_css(guard, dest),
-            CssRule::Property(ref lock) => lock.read_with(guard).to_css(guard, dest),
+            CssRule::Property(ref rule) => rule.to_css(guard, dest),
             CssRule::Document(ref lock) => lock.read_with(guard).to_css(guard, dest),
             CssRule::LayerBlock(ref lock) => lock.read_with(guard).to_css(guard, dest),
             CssRule::LayerStatement(ref lock) => lock.read_with(guard).to_css(guard, dest),
diff --git a/components/style/stylesheets/rule_parser.rs b/components/style/stylesheets/rule_parser.rs
index 8aee0326538..fd03f726efd 100644
--- a/components/style/stylesheets/rule_parser.rs
+++ b/components/style/stylesheets/rule_parser.rs
@@ -720,8 +720,11 @@ impl<'a, 'b, 'i> AtRuleParser<'i> for NestedRuleParser<'a, 'b, 'i> {
                 })))
             },
             AtRulePrelude::Property(name) => self.nest_for_rule(CssRuleType::Property, |p| {
-                CssRule::Property(Arc::new(p.shared_lock.wrap(
-                    parse_property_block(&p.context, input, name, start.source_location()),
+                CssRule::Property(Arc::new(parse_property_block(
+                    &p.context,
+                    input,
+                    name,
+                    start.source_location(),
                 )))
             }),
             AtRulePrelude::Document(condition) => {