diff --git a/Cargo.lock b/Cargo.lock
index 6940a50fb29..6a8f45644ae 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -336,7 +336,7 @@ dependencies = [
  "azure 0.21.0 (git+https://github.com/servo/rust-azure)",
  "canvas_traits 0.0.1",
  "compositing 0.0.1",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -352,7 +352,7 @@ dependencies = [
 name = "canvas_traits"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_derive 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -600,7 +600,7 @@ dependencies = [
 
 [[package]]
 name = "cssparser"
-version = "0.21.0"
+version = "0.21.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cssparser-macros 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1087,7 +1087,7 @@ name = "geckoservo"
 version = "0.0.1"
 dependencies = [
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1156,7 +1156,7 @@ dependencies = [
 name = "gfx_tests"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx 0.0.1",
  "ipc-channel 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
@@ -1749,7 +1749,7 @@ name = "malloc_size_of"
 version = "0.0.1"
 dependencies = [
  "app_units 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hashglobe 0.1.0",
  "servo_arc 0.0.1",
@@ -2579,7 +2579,7 @@ dependencies = [
  "caseless 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "cmake 0.1.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "cookie 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "deny_public_fields 0.0.1",
  "devtools_traits 0.0.1",
  "dom_struct 0.0.1",
@@ -2651,7 +2651,7 @@ dependencies = [
  "app_units 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "canvas_traits 0.0.1",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
  "heapsize 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2723,7 +2723,7 @@ name = "selectors"
 version = "0.19.0"
 dependencies = [
  "bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fnv 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
@@ -3128,7 +3128,7 @@ dependencies = [
  "bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "fallible 0.0.1",
@@ -3189,7 +3189,7 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "html5ever 0.19.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3211,7 +3211,7 @@ version = "0.0.1"
 dependencies = [
  "app_units 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_derive 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3228,7 +3228,7 @@ name = "stylo_tests"
 version = "0.0.1"
 dependencies = [
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "geckoservo 0.0.1",
@@ -3819,7 +3819,7 @@ dependencies = [
 "checksum core-foundation-sys 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "41115a6aa5d3e1e5ef98148373f25971d1fad53818553f216495f9e67e90a624"
 "checksum core-graphics 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a9f841e9637adec70838c537cae52cb4c751cc6514ad05669b51d107c2021c79"
 "checksum core-text 6.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "16ce16d9ed00181016c11ff48e561314bec92bfbce9fe48f319366618d4e5de6"
-"checksum cssparser 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e88f0308699ff4e42b2ae57f170673f180a5b41f59364c95ae5c0c8022dbcbd1"
+"checksum cssparser 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a1dbaec53fe0184bd20e3efd5cb36fcf3286ce4070181ae125ac5a137c7f7fd1"
 "checksum cssparser-macros 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "079adec4af52bb5275eadd004292028c79eb3c5f5b4ee8086a36d4197032f6df"
 "checksum darling 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9861a8495606435477df581bc858ccf15a3469747edf175b94a4704fd9aaedac"
 "checksum darling_core 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1486a8b00b45062c997f767738178b43219133dd0c8c826cb811e60563810821"
diff --git a/components/canvas/Cargo.toml b/components/canvas/Cargo.toml
index ac91c12a7c6..fbba07aed82 100644
--- a/components/canvas/Cargo.toml
+++ b/components/canvas/Cargo.toml
@@ -13,7 +13,7 @@ path = "lib.rs"
 azure = {git = "https://github.com/servo/rust-azure"}
 canvas_traits = {path = "../canvas_traits"}
 compositing = {path = "../compositing"}
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 fnv = "1.0"
 gleam = "0.4"
diff --git a/components/canvas_traits/Cargo.toml b/components/canvas_traits/Cargo.toml
index 3ac95080897..79cb182a5af 100644
--- a/components/canvas_traits/Cargo.toml
+++ b/components/canvas_traits/Cargo.toml
@@ -10,7 +10,7 @@ name = "canvas_traits"
 path = "lib.rs"
 
 [dependencies]
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 heapsize = "0.4"
 heapsize_derive = "0.1"
diff --git a/components/malloc_size_of/Cargo.toml b/components/malloc_size_of/Cargo.toml
index 7ddb45b774e..a47ef2d4c4c 100644
--- a/components/malloc_size_of/Cargo.toml
+++ b/components/malloc_size_of/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 
 [dependencies]
 app_units = "0.5.5"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 hashglobe = { path = "../hashglobe" }
 servo_arc = { path = "../servo_arc" }
diff --git a/components/script/Cargo.toml b/components/script/Cargo.toml
index 8bb61ec57cf..43f85a4e970 100644
--- a/components/script/Cargo.toml
+++ b/components/script/Cargo.toml
@@ -33,7 +33,7 @@ byteorder = "1.0"
 canvas_traits = {path = "../canvas_traits"}
 caseless = "0.1.0"
 cookie = "0.6"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 deny_public_fields = {path = "../deny_public_fields"}
 devtools_traits = {path = "../devtools_traits"}
 dom_struct = {path = "../dom_struct"}
diff --git a/components/script/dom/htmlmetaelement.rs b/components/script/dom/htmlmetaelement.rs
index dbf5b676879..462c4aafec1 100644
--- a/components/script/dom/htmlmetaelement.rs
+++ b/components/script/dom/htmlmetaelement.rs
@@ -110,6 +110,7 @@ impl HTMLMetaElement {
                             quirks_mode: document.quirks_mode(),
                             url_data: RwLock::new(window_from_node(self).get_url()),
                             source_map_url: RwLock::new(None),
+                            source_url: RwLock::new(None),
                         },
                         media: Arc::new(shared_lock.wrap(MediaList::empty())),
                         shared_lock: shared_lock.clone(),
diff --git a/components/script/stylesheet_loader.rs b/components/script/stylesheet_loader.rs
index 1e6b2470e5c..597fac81cf1 100644
--- a/components/script/stylesheet_loader.rs
+++ b/components/script/stylesheet_loader.rs
@@ -292,6 +292,7 @@ impl<'a> StyleStylesheetLoader for StylesheetLoader<'a> {
                 quirks_mode: context.quirks_mode,
                 namespaces: RwLock::new(Namespaces::default()),
                 source_map_url: RwLock::new(None),
+                source_url: RwLock::new(None),
             },
             media: media,
             shared_lock: lock.clone(),
diff --git a/components/script_layout_interface/Cargo.toml b/components/script_layout_interface/Cargo.toml
index 8a078aa643e..ef885c5fc37 100644
--- a/components/script_layout_interface/Cargo.toml
+++ b/components/script_layout_interface/Cargo.toml
@@ -13,7 +13,7 @@ path = "lib.rs"
 app_units = "0.5"
 atomic_refcell = "0.1"
 canvas_traits = {path = "../canvas_traits"}
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 gfx_traits = {path = "../gfx_traits"}
 heapsize = "0.4"
diff --git a/components/selectors/Cargo.toml b/components/selectors/Cargo.toml
index 3ae6e7feec5..0fa01f994b3 100644
--- a/components/selectors/Cargo.toml
+++ b/components/selectors/Cargo.toml
@@ -25,7 +25,7 @@ unstable = []
 [dependencies]
 bitflags = "0.7"
 matches = "0.1"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 log = "0.3"
 fnv = "1.0"
 malloc_size_of = { path = "../malloc_size_of" }
diff --git a/components/style/Cargo.toml b/components/style/Cargo.toml
index 3dc910a976f..827658bf077 100644
--- a/components/style/Cargo.toml
+++ b/components/style/Cargo.toml
@@ -37,7 +37,7 @@ atomic_refcell = "0.1"
 bitflags = "0.7"
 byteorder = "1.0"
 cfg-if = "0.1.0"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 encoding = {version = "0.2", optional = true}
 euclid = "0.15"
 fallible = { path = "../fallible" }
diff --git a/components/style/gecko/generated/bindings.rs b/components/style/gecko/generated/bindings.rs
index fdf32c538cd..3cc3094e4d9 100644
--- a/components/style/gecko/generated/bindings.rs
+++ b/components/style/gecko/generated/bindings.rs
@@ -1970,6 +1970,10 @@ extern "C" {
                                                 RawServoStyleSheetContentsBorrowed,
                                             result: *mut nsAString);
 }
+extern "C" {
+    pub fn Servo_StyleSheet_GetSourceURL(sheet: RawServoStyleSheetContentsBorrowed,
+                                         result: *mut nsAString);
+}
 extern "C" {
     pub fn Servo_StyleSheet_GetOrigin(sheet:
                                           RawServoStyleSheetContentsBorrowed)
diff --git a/components/style/stylesheets/stylesheet.rs b/components/style/stylesheets/stylesheet.rs
index eda245785a8..234f18cb003 100644
--- a/components/style/stylesheets/stylesheet.rs
+++ b/components/style/stylesheets/stylesheet.rs
@@ -62,6 +62,8 @@ pub struct StylesheetContents {
     pub quirks_mode: QuirksMode,
     /// This stylesheet's source map URL.
     pub source_map_url: RwLock<Option<String>>,
+    /// This stylesheet's source URL.
+    pub source_url: RwLock<Option<String>>,
 }
 
 impl StylesheetContents {
@@ -78,7 +80,7 @@ impl StylesheetContents {
         line_number_offset: u32
     ) -> Self {
         let namespaces = RwLock::new(Namespaces::default());
-        let (rules, source_map_url) = Stylesheet::parse_rules(
+        let (rules, source_map_url, source_url) = Stylesheet::parse_rules(
             css,
             &url_data,
             origin,
@@ -97,6 +99,7 @@ impl StylesheetContents {
             namespaces: namespaces,
             quirks_mode: quirks_mode,
             source_map_url: RwLock::new(source_map_url),
+            source_url: RwLock::new(source_url),
         }
     }
 
@@ -146,6 +149,7 @@ impl DeepCloneWithLock for StylesheetContents {
             url_data: RwLock::new((*self.url_data.read()).clone()),
             namespaces: RwLock::new((*self.namespaces.read()).clone()),
             source_map_url: RwLock::new((*self.source_map_url.read()).clone()),
+            source_url: RwLock::new((*self.source_map_url.read()).clone()),
         }
     }
 }
@@ -314,7 +318,7 @@ impl Stylesheet {
         where R: ParseErrorReporter
     {
         let namespaces = RwLock::new(Namespaces::default());
-        let (rules, source_map_url) =
+        let (rules, source_map_url, source_url) =
             Stylesheet::parse_rules(
                 css,
                 &url_data,
@@ -337,6 +341,7 @@ impl Stylesheet {
         let mut guard = existing.shared_lock.write();
         *existing.contents.rules.write_with(&mut guard) = CssRules(rules);
         *existing.contents.source_map_url.write() = source_map_url;
+        *existing.contents.source_url.write() = source_url;
     }
 
     fn parse_rules<R: ParseErrorReporter>(
@@ -349,7 +354,7 @@ impl Stylesheet {
         error_reporter: &R,
         quirks_mode: QuirksMode,
         line_number_offset: u32
-    ) -> (Vec<CssRule>, Option<String>) {
+    ) -> (Vec<CssRule>, Option<String>, Option<String>) {
         let mut rules = Vec::new();
         let mut input = ParserInput::new_with_line_number_offset(css, line_number_offset);
         let mut input = Parser::new(&mut input);
@@ -399,7 +404,8 @@ impl Stylesheet {
         }
 
         let source_map_url = input.current_source_map_url().map(String::from);
-        (rules, source_map_url)
+        let source_url = input.current_source_url().map(String::from);
+        (rules, source_map_url, source_url)
     }
 
     /// Creates an empty stylesheet and parses it with a given base url, origin
diff --git a/components/style_traits/Cargo.toml b/components/style_traits/Cargo.toml
index 5de57305ba3..40a2ad8e573 100644
--- a/components/style_traits/Cargo.toml
+++ b/components/style_traits/Cargo.toml
@@ -16,7 +16,7 @@ gecko = []
 [dependencies]
 app_units = "0.5"
 bitflags = "0.7"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 heapsize = {version = "0.4", optional = true}
 heapsize_derive = {version = "0.1", optional = true}
diff --git a/ports/geckolib/Cargo.toml b/ports/geckolib/Cargo.toml
index fd8b77ce697..fd711610a27 100644
--- a/ports/geckolib/Cargo.toml
+++ b/ports/geckolib/Cargo.toml
@@ -15,7 +15,7 @@ gecko_debug = ["style/gecko_debug"]
 
 [dependencies]
 atomic_refcell = "0.1"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 env_logger = {version = "0.4", default-features = false} # disable `regex` to reduce code size
 libc = "0.2"
 log = {version = "0.3.5", features = ["release_max_level_info"]}
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 2a0095d3d6e..6691ef07b7f 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -1120,6 +1120,18 @@ pub extern "C" fn Servo_StyleSheet_GetSourceMapURL(
     }
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_StyleSheet_GetSourceURL(
+    sheet: RawServoStyleSheetContentsBorrowed,
+    result: *mut nsAString
+) {
+    let contents = StylesheetContents::as_arc(&sheet);
+    let url_opt = contents.source_url.read();
+    if let Some(ref url) = *url_opt {
+        write!(unsafe { &mut *result }, "{}", url).unwrap();
+    }
+}
+
 fn read_locked_arc<T, R, F>(raw: &<Locked<T> as HasFFI>::FFIType, func: F) -> R
     where Locked<T>: HasArcFFI, F: FnOnce(&T) -> R
 {
diff --git a/tests/unit/gfx/Cargo.toml b/tests/unit/gfx/Cargo.toml
index 0e884926b01..2faab684a19 100644
--- a/tests/unit/gfx/Cargo.toml
+++ b/tests/unit/gfx/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 gfx = {path = "../../../components/gfx"}
 ipc-channel = "0.8"
 style = {path = "../../../components/style"}
diff --git a/tests/unit/style/Cargo.toml b/tests/unit/style/Cargo.toml
index a5bb083f4d0..29a04be4202 100644
--- a/tests/unit/style/Cargo.toml
+++ b/tests/unit/style/Cargo.toml
@@ -12,7 +12,7 @@ doctest = false
 [dependencies]
 byteorder = "1.0"
 app_units = "0.5"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 euclid = "0.15"
 html5ever = "0.19"
 parking_lot = "0.4"
diff --git a/tests/unit/style/stylesheets.rs b/tests/unit/style/stylesheets.rs
index 705945fd812..2490ba4cfbe 100644
--- a/tests/unit/style/stylesheets.rs
+++ b/tests/unit/style/stylesheets.rs
@@ -249,6 +249,7 @@ fn test_parse_stylesheet() {
                 })))
             ], &stylesheet.shared_lock),
             source_map_url: RwLock::new(None),
+            source_url: RwLock::new(None),
         },
         media: Arc::new(stylesheet.shared_lock.wrap(MediaList::empty())),
         shared_lock: stylesheet.shared_lock.clone(),
@@ -377,3 +378,22 @@ fn test_source_map_url() {
         assert_eq!(*url_opt, test.1);
     }
 }
+
+#[test]
+fn test_source_url() {
+    let tests = vec![
+        ("", None),
+        ("/*# sourceURL=something */", Some("something".to_string())),
+    ];
+
+    for test in tests {
+        let url = ServoUrl::parse("about::test").unwrap();
+        let lock = SharedRwLock::new();
+        let media = Arc::new(lock.wrap(MediaList::empty()));
+        let stylesheet = Stylesheet::from_str(test.0, url.clone(), Origin::UserAgent, media, lock,
+                                              None, &CSSErrorReporterTest, QuirksMode::NoQuirks,
+                                              0);
+        let url_opt = stylesheet.contents.source_url.read();
+        assert_eq!(*url_opt, test.1);
+    }
+}
diff --git a/tests/unit/stylo/Cargo.toml b/tests/unit/stylo/Cargo.toml
index 4a7528e6588..2d430835681 100644
--- a/tests/unit/stylo/Cargo.toml
+++ b/tests/unit/stylo/Cargo.toml
@@ -13,7 +13,7 @@ doctest = false
 
 [dependencies]
 atomic_refcell = "0.1"
-cssparser = "0.21.0"
+cssparser = "0.21.1"
 env_logger = "0.4"
 euclid = "0.15"
 geckoservo = {path = "../../../ports/geckolib"}