output should not match to :enabled or :disabled pseudo classes.

third_party/WebKit/Source/core/html/HTMLOutputElement.h

 /*
  * Copyright (c) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 44 matching lines @@
     bool canContainRangeEndPoint() const override { return false; }
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     HTMLOutputElement(Document&, HTMLFormElement*);
 
     void parseAttribute(const QualifiedName&, const AtomicString&, const AtomicString&) override;
     const AtomicString& formControlType() const override;
     bool isDisabledFormControl() const override;
+    bool matchesEnabledPseudoClass() const override;
     bool isEnumeratable() const override { return true; }
     bool supportLabels() const override { return true; }
     bool supportsFocus() const override;
     void childrenChanged(const ChildrenChange&) override;
     void resetImpl() override;
 
     void valueWasSet() final;
 
     bool m_isDefaultValueMode;
     String m_defaultValue;
     Member<DOMTokenList> m_tokens;
 };
 
 } // namespace blink
 
 #endif // HTMLOutputElement_h