diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index 81217e6..ff93693 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,17 @@
+2021-11-27  Antti Koivisto  <antti@apple.com>
+
+        [:has() pseudo-class] Invalidation support for adding and removing elements
+        https://bugs.webkit.org/show_bug.cgi?id=233489
+        <rdar://problem/85754298>
+
+        Unreviewed followup.
+
+        Some unitialized bits caused us to do unnecessary work and regressed Speedometer.
+
+        * style/RuleFeature.h:
+
+        Initialize the usedMatchElements array.
+
 2021-11-26  Sam Weinig  <weinig@apple.com>
 
         Typo in ColorConversion code: converColorComponents
diff --git a/Source/WebCore/style/RuleFeature.h b/Source/WebCore/style/RuleFeature.h
index 4debf88..8a129fe 100644
--- a/Source/WebCore/style/RuleFeature.h
+++ b/Source/WebCore/style/RuleFeature.h
@@ -86,7 +86,7 @@
     HashSet<AtomString> attributesAffectingHost;
     HashSet<CSSSelector::PseudoClassType, IntHash<CSSSelector::PseudoClassType>, WTF::StrongEnumHashTraits<CSSSelector::PseudoClassType>> pseudoClassesAffectingHost;
 
-    std::array<bool, matchElementCount> usedMatchElements;
+    std::array<bool, matchElementCount> usedMatchElements { };
 
     bool usesFirstLineRules { false };
     bool usesFirstLetterRules { false };