diff --git a/components/script/dom/htmlbuttonelement.rs b/components/script/dom/htmlbuttonelement.rs
index 0ba1cb740e4..0b40b97c5aa 100644
--- a/components/script/dom/htmlbuttonelement.rs
+++ b/components/script/dom/htmlbuttonelement.rs
@@ -22,7 +22,7 @@ use dom::node::{DisabledStateHelpers, Node, NodeHelpers, NodeTypeId, document_fr
 use dom::validitystate::ValidityState;
 use dom::virtualmethods::VirtualMethods;
 
-use std::ascii::OwnedAsciiExt;
+use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use util::str::DOMString;
 use std::cell::Cell;
@@ -86,7 +86,8 @@ impl<'a> HTMLButtonElementMethods for &'a HTMLButtonElement {
     // https://html.spec.whatwg.org/multipage/#dom-button-type
     fn Type(self) -> DOMString {
         let elem = ElementCast::from_ref(self);
-        let ty = elem.get_string_attribute(&atom!("type")).into_ascii_lowercase();
+        let mut ty = elem.get_string_attribute(&atom!("type"));
+        ty.make_ascii_lowercase();
         // https://html.spec.whatwg.org/multipage/#attr-button-type
         match &*ty {
             "reset" | "button" | "menu" => ty,
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index bfa5792327a..e0a948bbedf 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -35,7 +35,6 @@ use hyper::mime;
 use msg::constellation_msg::LoadData;
 use util::str::DOMString;
 use script_task::{ScriptChan, ScriptMsg};
-use std::ascii::OwnedAsciiExt;
 use url::UrlParser;
 use url::form_urlencoded::serialize;
 use string_cache::Atom;
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index 2f3db69b43d..e41fb1571b8 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -38,7 +38,6 @@ use msg::constellation_msg::ConstellationChan;
 use util::str::DOMString;
 use string_cache::Atom;
 
-use std::ascii::OwnedAsciiExt;
 use std::borrow::ToOwned;
 use std::cell::Cell;
 
diff --git a/components/script/dom/macros.rs b/components/script/dom/macros.rs
index 457989af969..6b19d3f99c0 100644
--- a/components/script/dom/macros.rs
+++ b/components/script/dom/macros.rs
@@ -104,9 +104,10 @@ macro_rules! make_enumerated_getter(
             use dom::bindings::codegen::InheritTypes::ElementCast;
             use string_cache::Atom;
             use std::borrow::ToOwned;
+            use std::ascii::AsciiExt;
             let element = ElementCast::from_ref(self);
-            let val = element.get_string_attribute(&Atom::from_slice($htmlname))
-                             .into_ascii_lowercase();
+            let mut val = element.get_string_attribute(&Atom::from_slice($htmlname));
+            val.make_ascii_lowercase();
             // https://html.spec.whatwg.org/multipage/#attr-fs-method
             match &*val {
                 $($choices)|+ => val,
diff --git a/components/script/lib.rs b/components/script/lib.rs
index 16f73c85afd..459eff4bd82 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -4,6 +4,7 @@
 
 #![feature(append)]
 #![feature(arc_unique)]
+#![feature(ascii)]
 #![feature(as_slice)]
 #![feature(as_unsafe_cell)]
 #![feature(borrow_state)]
@@ -17,7 +18,6 @@
 #![feature(hashmap_hasher)]
 #![feature(mpsc_select)]
 #![feature(nonzero)]
-#![feature(owned_ascii_ext)]
 #![feature(plugin)]
 #![feature(rc_unique)]
 #![feature(slice_chars)]