diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 9a2ab2135fc5..8e69a688e33d 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -1726,6 +1726,49 @@ fn static_assert() {
     pub fn reset_grid_template_areas(&mut self, other: &Self) {
         self.copy_grid_template_areas_from(other)
     }
+
+    pub fn clone_grid_template_areas(&self) -> longhands::grid_template_areas::computed_value::T {
+        use properties::longhands::grid_template_areas::{NamedArea, TemplateAreas};
+        use std::ops::Range;
+        use values::None_;
+
+        if self.gecko.mGridTemplateAreas.mRawPtr.is_null() {
+            return Either::Second(None_);
+        }
+
+        let gecko_grid_template_areas = self.gecko.mGridTemplateAreas.mRawPtr;
+        let areas = unsafe {
+            let vec: Vec<NamedArea> =
+                (*gecko_grid_template_areas).mNamedAreas.iter().map(|gecko_name_area| {
+                    let name = gecko_name_area.mName.to_string().into_boxed_str();
+                    let rows = Range {
+                        start: gecko_name_area.mRowStart,
+                        end: gecko_name_area.mRowEnd
+                    };
+                    let columns = Range {
+                        start: gecko_name_area.mColumnStart,
+                        end: gecko_name_area.mColumnEnd
+                    };
+                    NamedArea{ name, rows, columns }
+                }).collect();
+            vec.into_boxed_slice()
+        };
+
+        let strings = unsafe {
+            let vec: Vec<Box<str>> =
+                (*gecko_grid_template_areas).mTemplates.iter().map(|gecko_template| {
+                    gecko_template.to_string().into_boxed_str()
+                }).collect();
+            vec.into_boxed_slice()
+        };
+
+        let width = unsafe {
+            (*gecko_grid_template_areas).mNColumns
+        };
+
+        Either::First(TemplateAreas{ areas, strings, width })
+    }
+
 </%self:impl_trait>
 
 <% skip_outline_longhands = " ".join("outline-style outline-width".split() +
diff --git a/components/style/properties/longhand/position.mako.rs b/components/style/properties/longhand/position.mako.rs
index 780b7ebabcae..e970d99b9065 100644
--- a/components/style/properties/longhand/position.mako.rs
+++ b/components/style/properties/longhand/position.mako.rs
@@ -416,7 +416,7 @@ ${helpers.predefined_type("object-position",
 <%helpers:longhand name="grid-template-areas"
         spec="https://drafts.csswg.org/css-grid/#propdef-grid-template-areas"
         products="gecko"
-        animation_value_type="none"
+        animation_value_type="discrete"
         disable_when_testing="True"
         boxed="True">
     use std::collections::HashMap;
@@ -442,14 +442,14 @@ ${helpers.predefined_type("object-position",
         SpecifiedValue::parse(context, input)
     }
 
-    #[derive(Clone, PartialEq)]
+    #[derive(Clone, Debug, PartialEq)]
     pub struct TemplateAreas {
         pub areas: Box<[NamedArea]>,
         pub strings: Box<[Box<str>]>,
         pub width: u32,
     }
 
-    #[derive(Clone, PartialEq)]
+    #[derive(Clone, Debug, PartialEq)]
     pub struct NamedArea {
         pub name: Box<str>,
         pub rows: Range<u32>,