AngleSharp · FlorianRappl · Sep 12, 2026 · Sep 12, 2026 · Sep 12, 2026 · Sep 12, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# 1.1.3
+
+Released on Saturday, September 12 2026
+
+- Improved pseudo-class matching to skip a per-element `ConditionalWeakTable` probe when no state has ever been forced via `SetPseudoClass`
+
 # 1.1.2
 
 Released on Friday, September 11 2026

diff --git a/src/AngleSharp.Css.Docs/package.json b/src/AngleSharp.Css.Docs/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@anglesharp/css",
-  "version": "1.1.2",
+  "version": "1.1.3",
   "preview": true,
   "description": "The doclet for the AngleSharp.Css documentation.",
   "keywords": [

diff --git a/src/AngleSharp.Css/PseudoClassStateStore.cs b/src/AngleSharp.Css/PseudoClassStateStore.cs
@@ -14,12 +14,24 @@ static class PseudoClassStateStore
     {
         private static readonly ConditionalWeakTable<IElement, Dictionary<String, Boolean>> _states = new();
 
-        public static void Set(IElement element, String pseudoClass, Boolean value) =>
+        // WithCss() wraps every non-:focus pseudo-class selector in ForcingPseudoClassSelector, so
+        // TryGet runs once per pseudo-class match attempt on every element - a page that never
+        // calls SetPseudoClass still paid a ConditionalWeakTable probe for every :hover, :disabled,
+        // :checked, ... match. This flag only ever moves from "nothing forced" to "something
+        // forced": Remove/Clear cannot prove every forced state everywhere has been undone (there
+        // is no per-element or per-process count to check), so it deliberately never goes back to
+        // false. Once anything has been forced, the process pays the old per-match cost again.
+        private static volatile Boolean _anyForced;
+
+        public static void Set(IElement element, String pseudoClass, Boolean value)
+        {
+            _anyForced = true;
             _states.GetValue(element, _ => new Dictionary<String, Boolean>(StringComparer.OrdinalIgnoreCase))[pseudoClass] = value;
+        }
 
         public static Boolean TryGet(IElement element, String pseudoClass, out Boolean value)
         {
-            if (_states.TryGetValue(element, out var state) && state.TryGetValue(pseudoClass, out value))
+            if (_anyForced && _states.TryGetValue(element, out var state) && state.TryGetValue(pseudoClass, out value))
             {
                 return true;
             }

diff --git a/src/AngleSharp.Performance.Css/CssCascadeBenchmarks.cs b/src/AngleSharp.Performance.Css/CssCascadeBenchmarks.cs
@@ -124,6 +124,20 @@ private static String BuildDocument()
 
             sb.Append("h1,h2,h3,p.big,a:hover,.c-1 span{font-weight:bold;letter-spacing:0.02em;}");
             sb.Append(".hidden{display:none}.big{font-size:24px}a{color:blue}");
+
+            // WithCss() wraps every non-:focus pseudo-class selector so a caller-forced state
+            // (ElementExtensions.SetPseudoClass) can override it - so every rule below probes a
+            // ConditionalWeakTable per candidate element even though this benchmark never forces
+            // anything. One rule per child class per interaction pseudo-class keeps every sampled
+            // "div.child-*" reaching that probe instead of being short-circuited by an earlier,
+            // non-matching simple selector.
+            for (var i = 0; i < 20; i++)
+            {
+                sb.Append(".child-").Append(i).Append(":hover{outline:1px solid red;}");
+                sb.Append(".child-").Append(i).Append(":active{outline:1px solid green;}");
+                sb.Append(".child-").Append(i).Append(":disabled{outline:1px solid blue;}");
+            }
+
             sb.Append("</style></head><body><main id='root'>");
 
             for (var s = 0; s < 25; s++)

diff --git a/src/Directory.Build.props b/src/Directory.Build.props
@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Description>Extends the CSSOM from the core AngleSharp library.</Description>
     <Product>AngleSharp.Css</Product>
-    <Version>1.1.2</Version>
+    <Version>1.1.3</Version>
     <Nullable>enable</Nullable>
     <LangVersion>latest</LangVersion>
     <SignAssembly>true</SignAssembly>