diff --git a/components/style/properties.mako.rs b/components/style/properties.mako.rs
index ce285c4d71b..0b9dcd11217 100644
--- a/components/style/properties.mako.rs
+++ b/components/style/properties.mako.rs
@@ -6722,10 +6722,8 @@ pub type CascadePropertyFn<C /*: ComputedValues */> =
                      cacheable: &mut bool,
                      error_reporter: &mut Box<ParseErrorReporter + Send>);
 
-// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
-// properties.
-thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
-    let mut result: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = Vec::new();
+pub fn make_cascade_vec<C: ComputedValues>() -> Vec<Option<CascadePropertyFn<C>>> {
+    let mut result: Vec<Option<CascadePropertyFn<C>>> = Vec::new();
     % for style_struct in STYLE_STRUCTS:
         % for property in style_struct.longhands:
             let discriminant;
@@ -6741,6 +6739,12 @@ thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoCompute
         % endfor
     % endfor
     result
+}
+
+// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
+// properties.
+thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
+    make_cascade_vec::<ServoComputedValues>()
 });
 
 /// Performs the CSS cascade, computing new styles for an element from its parent style and
diff --git a/ports/geckolib/properties.mako.rs b/ports/geckolib/properties.mako.rs
index 38e3b0ead44..94407b18c8f 100644
--- a/ports/geckolib/properties.mako.rs
+++ b/ports/geckolib/properties.mako.rs
@@ -19,6 +19,7 @@ use style::custom_properties::ComputedValuesMap;
 use style::logical_geometry::WritingMode;
 use style::properties::{CascadePropertyFn, ServoComputedValues, ComputedValues};
 use style::properties::longhands;
+use style::properties::make_cascade_vec;
 use style::properties::style_struct_traits::*;
 
 #[derive(Clone)]
@@ -63,8 +64,8 @@ impl ComputedValues for GeckoComputedValues {
 
     fn initial_values() -> &'static Self { &*INITIAL_GECKO_VALUES }
 
-    fn do_cascade_property<F: FnOnce(&Vec<Option<CascadePropertyFn<Self>>>)>(_: F) {
-        unimplemented!()
+    fn do_cascade_property<F: FnOnce(&Vec<Option<CascadePropertyFn<Self>>>)>(f: F) {
+        CASCADE_PROPERTY.with(|x| f(x));
     }
 
     % for style_struct in STYLE_STRUCTS:
@@ -229,3 +230,9 @@ lazy_static! {
         root_font_size: longhands::font_size::get_initial_value(),
     };
 }
+
+// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
+// properties.
+thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<GeckoComputedValues>>> = {
+    make_cascade_vec::<GeckoComputedValues>()
+});