diff --git a/components/style/gecko/media_features.rs b/components/style/gecko/media_features.rs
index 614d12135d8..f44fd788b00 100644
--- a/components/style/gecko/media_features.rs
+++ b/components/style/gecko/media_features.rs
@@ -585,7 +585,7 @@ macro_rules! bool_pref_feature {
 /// to support new types in these entries and (2) ensuring that either
 /// nsPresContext::MediaFeatureValuesChanged is called when the value that
 /// would be returned by the evaluator function could change.
-pub static MEDIA_FEATURES: [QueryFeatureDescription; 61] = [
+pub static MEDIA_FEATURES: [QueryFeatureDescription; 62] = [
     feature!(
         atom!("width"),
         AllowsRanges::Yes,
@@ -885,4 +885,9 @@ pub static MEDIA_FEATURES: [QueryFeatureDescription; 61] = [
         atom!("-moz-mathml-core-maction-and-semantics"),
         "mathml.legacy_maction_and_semantics_implementations.disabled"
     ),
+    // media query for MathML Core's implementation of ms
+    bool_pref_feature!(
+        atom!("-moz-mathml-core-ms"),
+        "mathml.ms_lquote_rquote_attributes.disabled"
+    ),
 ];