diff --git a/components/style/animation.rs b/components/style/animation.rs
index 0e82b986f94..d6604b40db5 100644
--- a/components/style/animation.rs
+++ b/components/style/animation.rs
@@ -235,7 +235,7 @@ pub fn maybe_start_animations<Impl: SelectorImplExt>(context: &SharedStyleContex
         }
 
         // TODO: This should be factored out, too much indentation.
-        if let Some(ref animation) = context.stylist.animations().get(&**name) {
+        if let Some(ref animation) = context.stylist.animations().get(&name) {
             debug!("maybe_start_animations: found animation {}", name);
             had_animations = true;
             let mut last_keyframe_style = compute_style_for_animation_step(context,
diff --git a/components/style/properties/longhand/box.mako.rs b/components/style/properties/longhand/box.mako.rs
index bdd1d3d3aa5..4be64fd50aa 100644
--- a/components/style/properties/longhand/box.mako.rs
+++ b/components/style/properties/longhand/box.mako.rs
@@ -589,9 +589,10 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto", need_clone=
     pub mod computed_value {
         use cssparser::ToCss;
         use std::fmt;
+        use string_cache::Atom;
 
         #[derive(Debug, Clone, PartialEq, HeapSizeOf)]
-        pub struct T(pub Vec<String>);
+        pub struct T(pub Vec<Atom>);
 
         impl ToCss for T {
             fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
@@ -603,7 +604,8 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto", need_clone=
                     if i != 0 {
                         try!(dest.write_str(", "));
                     }
-                    try!(dest.write_str(&name));
+                    // NB: to_string() needed due to geckolib backend.
+                    try!(dest.write_str(&*name.to_string()));
                 }
                 Ok(())
             }
@@ -620,7 +622,7 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto", need_clone=
     pub fn parse(_: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue,()> {
         use std::borrow::Cow;
         Ok(SpecifiedValue(try!(input.parse_comma_separated(|input| {
-            input.expect_ident().map(Cow::into_owned)
+            input.expect_ident().map(Atom::from)
         }))))
     }
 
diff --git a/components/style/selector_matching.rs b/components/style/selector_matching.rs
index 676b78de08e..a4895e91ecb 100644
--- a/components/style/selector_matching.rs
+++ b/components/style/selector_matching.rs
@@ -24,6 +24,7 @@ use std::collections::HashMap;
 use std::hash::BuildHasherDefault;
 use std::process;
 use std::sync::Arc;
+use string_cache::Atom;
 use style_traits::viewport::ViewportConstraints;
 use stylesheets::{CSSRule, CSSRuleIteratorExt, Origin, Stylesheet};
 use url::Url;
@@ -129,7 +130,7 @@ pub struct Stylist<Impl: SelectorImplExt> {
                          BuildHasherDefault<::fnv::FnvHasher>>,
 
     /// A map with all the animations indexed by name.
-    animations: HashMap<String, KeyframesAnimation>,
+    animations: HashMap<Atom, KeyframesAnimation>,
 
     /// Applicable declarations for a given non-eagerly cascaded pseudo-element.
     /// These are eagerly computed once, and then used to resolve the new
@@ -461,7 +462,7 @@ impl<Impl: SelectorImplExt> Stylist<Impl> {
     }
 
     #[inline]
-    pub fn animations(&self) -> &HashMap<String, KeyframesAnimation> {
+    pub fn animations(&self) -> &HashMap<Atom, KeyframesAnimation> {
         &self.animations
     }
 }
diff --git a/components/style/stylesheets.rs b/components/style/stylesheets.rs
index c4a2ca24c3b..726db0251cf 100644
--- a/components/style/stylesheets.rs
+++ b/components/style/stylesheets.rs
@@ -69,7 +69,7 @@ pub enum CSSRule<Impl: SelectorImpl> {
 
 #[derive(Debug, HeapSizeOf, PartialEq)]
 pub struct KeyframesRule {
-    pub name: String,
+    pub name: Atom,
     pub keyframes: Vec<Keyframe>,
 }
 
@@ -405,7 +405,7 @@ enum AtRulePrelude {
     /// A @viewport rule prelude.
     Viewport,
     /// A @keyframes rule, with its animation name.
-    Keyframes(String),
+    Keyframes(Atom),
 }
 
 
@@ -507,7 +507,7 @@ impl<'a, 'b, Impl: SelectorImpl> AtRuleParser for NestedRuleParser<'a, 'b, Impl>
             },
             "keyframes" => {
                 let name = try!(input.expect_ident());
-                Ok(AtRuleType::WithBlock(AtRulePrelude::Keyframes(name.into_owned())))
+                Ok(AtRuleType::WithBlock(AtRulePrelude::Keyframes(Atom::from(name))))
             },
             _ => Err(())
         }