diff --git a/components/style/properties/longhand/font.mako.rs b/components/style/properties/longhand/font.mako.rs
index 59523c5a2a0..f83a536166e 100644
--- a/components/style/properties/longhand/font.mako.rs
+++ b/components/style/properties/longhand/font.mako.rs
@@ -173,6 +173,7 @@ ${helpers.single_keyword("font-variant", "normal small-caps")}
     pub mod computed_value {
         use std::fmt;
         #[derive(PartialEq, Eq, Copy, Clone, Hash, Deserialize, Serialize, HeapSizeOf, Debug)]
+        #[repr(u16)]
         pub enum T {
             % for weight in range(100, 901, 100):
                 Weight${weight} = ${weight},
diff --git a/ports/geckolib/properties.mako.rs b/ports/geckolib/properties.mako.rs
index 47d4b5c7d72..ff7ddd9a40c 100644
--- a/ports/geckolib/properties.mako.rs
+++ b/ports/geckolib/properties.mako.rs
@@ -424,7 +424,7 @@ fn static_assert() {
     }
 </%self:impl_trait>
 
-<%self:impl_trait style_struct_name="Font" skip_longhands="font-size" skip_additionals="*">
+<%self:impl_trait style_struct_name="Font" skip_longhands="font-size font-weight" skip_additionals="*">
 
     // FIXME(bholley): Gecko has two different sizes, one of which (mSize) is the
     // actual computed size, and the other of which (mFont.size) is the 'display
@@ -441,6 +441,18 @@ fn static_assert() {
         Au(self.gecko.mSize)
     }
 
+    fn set_font_weight(&mut self, v: longhands::font_weight::computed_value::T) {
+        self.gecko.mFont.weight = v as u16;
+    }
+    <%call expr="impl_simple_copy('font_weight', 'mFont.weight')"></%call>
+
+    fn clone_font_weight(&self) -> longhands::font_weight::computed_value::T {
+        debug_assert!(self.gecko.mFont.weight >= 100);
+        debug_assert!(self.gecko.mFont.weight <= 900);
+        debug_assert!(self.gecko.mFont.weight % 10 == 0);
+        unsafe { transmute(self.gecko.mFont.weight) }
+    }
+
     // This is used for PartialEq, which we don't implement for gecko style structs.
     fn compute_font_hash(&mut self) {}