diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index a95822e75814..2247e9290785 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -962,7 +962,8 @@ fn static_assert() {
 
 <% skip_box_longhands= """display overflow-y vertical-align
                           -moz-binding page-break-before page-break-after
-                          scroll-snap-points-x scroll-snap-points-y transform""" %>
+                          scroll-snap-points-x scroll-snap-points-y transform
+                          scroll-snap-type-y""" %>
 <%self:impl_trait style_struct_name="Box" skip_longhands="${skip_box_longhands}">
 
     // We manually-implement the |display| property until we get general
@@ -1204,6 +1205,11 @@ fn static_assert() {
     pub fn copy_transform_from(&mut self, other: &Self) {
         unsafe { self.gecko.mSpecifiedTransform.set(&other.gecko.mSpecifiedTransform); }
     }
+
+    <% scroll_snap_type_keyword = Keyword("scroll-snap-type", "none mandatory proximity") %>
+
+    ${impl_keyword('scroll_snap_type_y', 'mScrollSnapTypeY', scroll_snap_type_keyword, need_clone=False)}
+
 </%self:impl_trait>
 
 <%def name="simple_image_array_property(name, shorthand, field_name)">
diff --git a/components/style/properties/longhand/box.mako.rs b/components/style/properties/longhand/box.mako.rs
index 41ab2e5909c0..fc16ba267d78 100644
--- a/components/style/properties/longhand/box.mako.rs
+++ b/components/style/properties/longhand/box.mako.rs
@@ -1474,11 +1474,12 @@ ${helpers.single_keyword("scroll-snap-type-x",
                          animatable=False)}
 
 // Non-standard: https://developer.mozilla.org/en-US/docs/Web/CSS/scroll-snap-type-y
-${helpers.single_keyword("scroll-snap-type-y",
-                         "none mandatory proximity",
-                         products="gecko",
-                         gecko_constant_prefix="NS_STYLE_SCROLL_SNAP_TYPE",
-                         animatable=False)}
+<%helpers:longhand products="gecko" name="scroll-snap-type-y" animatable="False">
+    pub use super::scroll_snap_type_x::SpecifiedValue;
+    pub use super::scroll_snap_type_x::computed_value;
+    pub use super::scroll_snap_type_x::get_initial_value;
+    pub use super::scroll_snap_type_x::parse;
+</%helpers:longhand>
 
 // Compositing and Blending Level 1
 // http://www.w3.org/TR/compositing-1/