diff --git a/components/style/gecko_bindings/bindings.rs b/components/style/gecko_bindings/bindings.rs
index f2a2c19f1a5..adeecc3925d 100644
--- a/components/style/gecko_bindings/bindings.rs
+++ b/components/style/gecko_bindings/bindings.rs
@@ -932,6 +932,11 @@ extern "C" {
                                          b: RawServoDeclarationBlockBorrowed)
      -> bool;
 }
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetCssText(declarations:
+                                                 RawServoDeclarationBlockBorrowed,
+                                             result: *mut nsAString_internal);
+}
 extern "C" {
     pub fn Servo_DeclarationBlock_SerializeOneValue(declarations:
                                                         RawServoDeclarationBlockBorrowed,
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index b266a4c7084..4e3062faa0b 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -26,9 +26,9 @@ use style::gecko_bindings::bindings::{RawServoStyleSetBorrowed, RawServoStyleSet
 use style::gecko_bindings::bindings::{RawServoStyleSheetBorrowed, ServoComputedValuesBorrowed};
 use style::gecko_bindings::bindings::{RawServoStyleSheetStrong, ServoComputedValuesStrong};
 use style::gecko_bindings::bindings::{ThreadSafePrincipalHolder, ThreadSafeURIHolder};
+use style::gecko_bindings::bindings::{nsACString, nsAString};
 use style::gecko_bindings::bindings::Gecko_Utf8SliceToString;
 use style::gecko_bindings::bindings::ServoComputedValuesBorrowedOrNull;
-use style::gecko_bindings::bindings::nsACString;
 use style::gecko_bindings::structs::{SheetParsingMode, nsIAtom};
 use style::gecko_bindings::structs::ServoElementSnapshot;
 use style::gecko_bindings::structs::nsRestyleHint;
@@ -443,6 +443,13 @@ pub extern "C" fn Servo_DeclarationBlock_Equals(a: RawServoDeclarationBlockBorro
     *RwLock::<PropertyDeclarationBlock>::as_arc(&a).read() == *RwLock::<PropertyDeclarationBlock>::as_arc(&b).read()
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetCssText(declarations: RawServoDeclarationBlockBorrowed,
+                                                    result: *mut nsAString) {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    declarations.read().to_css(unsafe { result.as_mut().unwrap() }).unwrap();
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_DeclarationBlock_SerializeOneValue(
     declarations: RawServoDeclarationBlockBorrowed,