diff --git a/Libraries/LibJS/Script.h b/Libraries/LibJS/Script.h
index 53bbb628a52..aabb896d31c 100644
--- a/Libraries/LibJS/Script.h
+++ b/Libraries/LibJS/Script.h
@@ -24,6 +24,14 @@ public:
         virtual ~HostDefined() = default;
 
         virtual void visit_host_defined_self(Cell::Visitor&) = 0;
+
+        template<typename T>
+        bool fast_is() const = delete;
+
+        virtual bool is_script() const { return false; }
+        virtual bool is_classic_script() const { return false; }
+        virtual bool is_module_script() const { return false; }
+        virtual bool is_javascript_module_script() const { return false; }
     };
 
     virtual ~Script() override;
diff --git a/Libraries/LibWeb/HTML/Scripting/ClassicScript.h b/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
index 04909b19e9c..88dcb1b7fa6 100644
--- a/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
+++ b/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
@@ -40,6 +40,8 @@ public:
 private:
     ClassicScript(URL::URL base_url, ByteString filename, JS::Realm&);
 
+    virtual bool is_classic_script() const final { return true; }
+
     virtual void visit_edges(Cell::Visitor&) override;
 
     GC::Ptr<JS::Script> m_script_record;
@@ -47,3 +49,6 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Script::HostDefined::fast_is<Web::HTML::ClassicScript>() const { return is_classic_script(); }
diff --git a/Libraries/LibWeb/HTML/Scripting/ModuleScript.h b/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
index 7a3fc9ff0f9..664b962790d 100644
--- a/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
+++ b/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
@@ -20,6 +20,9 @@ public:
 
 protected:
     ModuleScript(URL::URL base_url, ByteString filename, JS::Realm&);
+
+private:
+    virtual bool is_module_script() const final { return true; }
 };
 
 class JavaScriptModuleScript final : public ModuleScript {
@@ -45,6 +48,7 @@ protected:
     JavaScriptModuleScript(URL::URL base_url, ByteString filename, JS::Realm&);
 
 private:
+    virtual bool is_javascript_module_script() const final { return true; }
     virtual void visit_edges(JS::Cell::Visitor&) override;
 
     GC::Ptr<JS::SourceTextModule> m_record;
@@ -56,3 +60,9 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Script::HostDefined::fast_is<Web::HTML::ModuleScript>() const { return is_module_script(); }
+
+template<>
+inline bool JS::Script::HostDefined::fast_is<Web::HTML::JavaScriptModuleScript>() const { return is_javascript_module_script(); }
diff --git a/Libraries/LibWeb/HTML/Scripting/Script.h b/Libraries/LibWeb/HTML/Scripting/Script.h
index 86e3eb5f1f2..4d33ec621dc 100644
--- a/Libraries/LibWeb/HTML/Scripting/Script.h
+++ b/Libraries/LibWeb/HTML/Scripting/Script.h
@@ -42,6 +42,7 @@ protected:
     virtual void visit_edges(Visitor&) override;
 
 private:
+    virtual bool is_script() const final { return true; }
     virtual void visit_host_defined_self(JS::Cell::Visitor&) override;
 
     Optional<URL::URL> m_base_url;
@@ -56,3 +57,6 @@ private:
 };
 
 }
+
+template<>
+inline bool JS::Script::HostDefined::fast_is<Web::HTML::Script>() const { return is_script(); }