diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 3ff3be2a2ec..5a2418112c8 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -1433,7 +1433,7 @@ fn static_assert() {
                 Gecko_NewGridTemplateAreasValue(v.0.areas.len() as u32, v.0.strings.len() as u32, v.0.width))
         };
 
-        for (servo, gecko) in v.0.areas.into_iter().zip(refptr.mNamedAreas.iter_mut()) {
+        for (servo, gecko) in v.0.areas.iter().zip(refptr.mNamedAreas.iter_mut()) {
             gecko.mName.assign_str(&*servo.name);
             gecko.mColumnStart = servo.columns.start;
             gecko.mColumnEnd = servo.columns.end;
@@ -1441,7 +1441,7 @@ fn static_assert() {
             gecko.mRowEnd = servo.rows.end;
         }
 
-        for (servo, gecko) in v.0.strings.into_iter().zip(refptr.mTemplates.iter_mut()) {
+        for (servo, gecko) in v.0.strings.iter().zip(refptr.mTemplates.iter_mut()) {
             gecko.assign_str(&*servo);
         }
 
@@ -1457,9 +1457,8 @@ fn static_assert() {
     }
 
     pub fn clone_grid_template_areas(&self) -> values::computed::position::GridTemplateAreas {
-        use std::ops::Range;
         use crate::values::None_;
-        use crate::values::specified::position::{NamedArea, TemplateAreas, TemplateAreasArc};
+        use crate::values::specified::position::{NamedArea, TemplateAreas, TemplateAreasArc, UnsignedRange};
 
         if self.gecko.mGridTemplateAreas.mRawPtr.is_null() {
             return Either::Second(None_);
@@ -1469,33 +1468,33 @@ fn static_assert() {
         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 {
+                    let name = gecko_name_area.mName.to_string().into();
+                    let rows = UnsignedRange {
                         start: gecko_name_area.mRowStart,
                         end: gecko_name_area.mRowEnd
                     };
-                    let columns = Range {
+                    let columns = UnsignedRange {
                         start: gecko_name_area.mColumnStart,
                         end: gecko_name_area.mColumnEnd
                     };
-                    NamedArea{ name, rows, columns }
+                    NamedArea { name, rows, columns }
                 }).collect();
-            vec.into_boxed_slice()
+            vec.into()
         };
 
         let strings = unsafe {
-            let vec: Vec<Box<str>> =
+            let vec: Vec<crate::OwnedStr> =
                 (*gecko_grid_template_areas).mTemplates.iter().map(|gecko_template| {
-                    gecko_template.to_string().into_boxed_str()
+                    gecko_template.to_string().into()
                 }).collect();
-            vec.into_boxed_slice()
+            vec.into()
         };
 
         let width = unsafe {
             (*gecko_grid_template_areas).mNColumns
         };
 
-        Either::First(TemplateAreasArc(Arc::new(TemplateAreas{ areas, strings, width })))
+        Either::First(TemplateAreasArc(Arc::new(TemplateAreas { areas, strings, width })))
     }
 
 </%self:impl_trait>
diff --git a/components/style/properties/shorthands/position.mako.rs b/components/style/properties/shorthands/position.mako.rs
index 63298b86ba1..73d47e1bea7 100644
--- a/components/style/properties/shorthands/position.mako.rs
+++ b/components/style/properties/shorthands/position.mako.rs
@@ -290,7 +290,7 @@
         % endfor
 
         let first_line_names = input.try(parse_line_names).unwrap_or(vec![].into_boxed_slice());
-        if let Ok(mut string) = input.try(|i| i.expect_string().map(|s| s.as_ref().into())) {
+        if let Ok(mut string) = input.try(|i| i.expect_string().map(|s| s.as_ref().to_owned().into())) {
             let mut strings = vec![];
             let mut values = vec![];
             let mut line_names = vec![];
@@ -305,7 +305,7 @@
                     names.extend(v.into_vec());
                 }
 
-                string = match input.try(|i| i.expect_string().map(|s| s.as_ref().into())) {
+                string = match input.try(|i| i.expect_string().map(|s| s.as_ref().to_owned().into())) {
                     Ok(s) => s,
                     _ => {      // only the named area determines whether we should bail out
                         line_names.push(names.into_boxed_slice());
@@ -323,7 +323,7 @@
                 .map_err(|()| input.new_custom_error(StyleParseErrorKind::UnspecifiedError))?;
             let template_rows = TrackList {
                 list_type: TrackListType::Normal,
-                values: values,
+                values,
                 line_names: line_names.into_boxed_slice(),
                 auto_repeat: None,
             };
diff --git a/components/style/values/specified/position.rs b/components/style/values/specified/position.rs
index fed0c5d3098..9f1fa7f2ee4 100644
--- a/components/style/values/specified/position.rs
+++ b/components/style/values/specified/position.rs
@@ -21,7 +21,6 @@ use cssparser::Parser;
 use selectors::parser::SelectorParseErrorKind;
 use servo_arc::Arc;
 use std::fmt::{self, Write};
-use std::ops::Range;
 use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
 
 /// The specified value of a CSS `<position>`
@@ -482,10 +481,10 @@ impl From<GridAutoFlow> for u8 {
 pub struct TemplateAreas {
     /// `named area` containing for each template area
     #[css(skip)]
-    pub areas: Box<[NamedArea]>,
+    pub areas: crate::OwnedSlice<NamedArea>,
     /// The original CSS string value of each template area
     #[css(iterable)]
-    pub strings: Box<[Box<str>]>,
+    pub strings: crate::OwnedSlice<crate::OwnedStr>,
     /// The number of columns of the grid.
     #[css(skip)]
     pub width: u32,
@@ -493,7 +492,7 @@ pub struct TemplateAreas {
 
 impl TemplateAreas {
     /// Transform `vector` of str into `template area`
-    pub fn from_vec(strings: Vec<Box<str>>) -> Result<TemplateAreas, ()> {
+    pub fn from_vec(strings: Vec<crate::OwnedStr>) -> Result<Self, ()> {
         if strings.is_empty() {
             return Err(());
         }
@@ -539,9 +538,15 @@ impl TemplateAreas {
                     }
                     let index = areas.len();
                     areas.push(NamedArea {
-                        name: token.to_owned().into_boxed_str(),
-                        columns: column..(column + 1),
-                        rows: row..(row + 1),
+                        name: token.to_owned().into(),
+                        columns: UnsignedRange {
+                            start: column,
+                            end: column + 1,
+                        },
+                        rows: UnsignedRange {
+                            start: row,
+                            end: row + 1,
+                        },
                     });
                     assert!(area_indices.insert(token, index).is_none());
                     current_area_index = Some(index);
@@ -560,8 +565,8 @@ impl TemplateAreas {
             }
         }
         Ok(TemplateAreas {
-            areas: areas.into_boxed_slice(),
-            strings: strings.into_boxed_slice(),
+            areas: areas.into(),
+            strings: strings.into(),
             width: width,
         })
     }
@@ -573,7 +578,7 @@ impl Parse for TemplateAreas {
         input: &mut Parser<'i, 't>,
     ) -> Result<Self, ParseError<'i>> {
         let mut strings = vec![];
-        while let Ok(string) = input.try(|i| i.expect_string().map(|s| s.as_ref().into())) {
+        while let Ok(string) = input.try(|i| i.expect_string().map(|s| s.as_ref().to_owned().into())) {
             strings.push(string);
         }
 
@@ -602,21 +607,31 @@ impl Parse for TemplateAreasArc {
         input: &mut Parser<'i, 't>,
     ) -> Result<Self, ParseError<'i>> {
         let parsed = TemplateAreas::parse(context, input)?;
-
         Ok(TemplateAreasArc(Arc::new(parsed)))
     }
 }
 
+/// A range of rows or columns. Using this instead of std::ops::Range for FFI
+/// purposes.
+#[repr(C)]
+#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToShmem)]
+pub struct UnsignedRange {
+    /// The start of the range.
+    pub start: u32,
+    /// The end of the range.
+    pub end: u32,
+}
+
 #[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToShmem)]
 /// Not associated with any particular grid item, but can
 /// be referenced from the grid-placement properties.
 pub struct NamedArea {
     /// Name of the `named area`
-    pub name: Box<str>,
+    pub name: crate::OwnedStr,
     /// Rows of the `named area`
-    pub rows: Range<u32>,
+    pub rows: UnsignedRange,
     /// Columns of the `named area`
-    pub columns: Range<u32>,
+    pub columns: UnsignedRange,
 }
 
 /// Tokenize the string into a list of the tokens,