--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -4309,18 +4309,16 @@ nsresult HTMLMediaElement::BindToTree(ns
       !IsEditable();
     // The preload action depends on the value of the autoplay attribute.
     // It's value may have changed, so update it.
     UpdatePreloadAction();
     aDocument->AddMediaContent(this);
   }
 
   if (mDecoder) {
-    // When the MediaElement is binding to tree, the dormant status is
-    // aligned to document's hidden status.
     mDecoder->NotifyOwnerActivityChanged(!IsHidden());
   }
 
   return rv;
 }
 
 /* static */
 void HTMLMediaElement::VideoDecodeSuspendTimerCallback(nsITimer* aTimer, void* aClosure)