--- a/dom/media/TextTrackCue.h
+++ b/dom/media/TextTrackCue.h
@@ -339,17 +339,22 @@ public:
    * content.
    */
   already_AddRefed<DocumentFragment> GetCueAsHTML();
 
   void SetTrackElement(HTMLTrackElement* aTrackElement);
 
   void SetActive(bool aActive)
   {
+    if (mActive == aActive) {
+      return;
+    }
+
     mActive = aActive;
+    mDisplayState = mActive ? mDisplayState : nullptr;
   }
 
   bool GetActive()
   {
     return mActive;
   }
 
 private: