diff --git a/components/config/prefs.rs b/components/config/prefs.rs
index a9ec112e3eb..64dd9659e56 100644
--- a/components/config/prefs.rs
+++ b/components/config/prefs.rs
@@ -99,7 +99,6 @@ pub struct Preferences {
     pub dom_serviceworker_timeout_seconds: i64,
     pub dom_servo_helpers_enabled: bool,
     pub dom_servoparser_async_html_tokenizer_enabled: bool,
-    pub dom_shadowdom_enabled: bool,
     pub dom_svg_enabled: bool,
     pub dom_testable_crash_enabled: bool,
     pub dom_testbinding_enabled: bool,
@@ -277,7 +276,6 @@ impl Preferences {
             dom_serviceworker_timeout_seconds: 60,
             dom_servo_helpers_enabled: false,
             dom_servoparser_async_html_tokenizer_enabled: false,
-            dom_shadowdom_enabled: true,
             dom_svg_enabled: false,
             dom_testable_crash_enabled: false,
             dom_testbinding_enabled: false,
diff --git a/components/script_bindings/webidls/Element.webidl b/components/script_bindings/webidls/Element.webidl
index 42733b91929..4545b18d058 100644
--- a/components/script_bindings/webidls/Element.webidl
+++ b/components/script_bindings/webidls/Element.webidl
@@ -84,7 +84,7 @@ interface Element : Node {
   [CEReactions, Throws]
   undefined insertAdjacentHTML(DOMString position, (TrustedHTML or DOMString) string);
 
-  [Throws, Pref="dom_shadowdom_enabled"] ShadowRoot attachShadow(ShadowRootInit init);
+  [Throws] ShadowRoot attachShadow(ShadowRootInit init);
   readonly attribute ShadowRoot? shadowRoot;
 };