--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -4824,17 +4824,17 @@ void HTMLMediaElement::FireTimeUpdate(bo
     mDecoder->SetFragmentEndTime(mFragmentEnd);
   }
 
   // Update the cues displaying on the video.
   // Here mTextTrackManager can be null if the cycle collector has unlinked
   // us before our parent. In that case UnbindFromTree will call us
   // when our parent is unlinked.
   if (mTextTrackManager) {
-    mTextTrackManager->UpdateCueDisplay();
+    mTextTrackManager->TimeMarchesOn();
   }
 }
 
 void HTMLMediaElement::GetCurrentSpec(nsCString& aString)
 {
   if (mLoadingSrc) {
     mLoadingSrc->GetSpec(aString);
   } else {

--- a/dom/html/TextTrackManager.cpp
+++ b/dom/html/TextTrackManager.cpp
@@ -247,20 +247,16 @@ TextTrackManager::UpdateCueDisplay()
 
     nsPIDOMWindowInner* window = mMediaElement->OwnerDoc()->GetInnerWindow();
     if (window) {
       sParserWrapper->ProcessCues(window, jsCues, overlay);
     }
   } else if (overlay->Length() > 0) {
     nsContentUtils::SetNodeTextContent(overlay, EmptyString(), true);
   }
-  // Call TimeMarchesOn() directly instead DispatchTimeMarchesOn()
-  // because we had render the new cue, so we must run
-  // TimeMarchesOn immediately.
-  TimeMarchesOn();
 }
 
 void
 TextTrackManager::AddCue(TextTrackCue& aCue)
 {
   if (mNewCues) {
     mNewCues->AddCue(aCue);
   }
@@ -534,17 +530,17 @@ TextTrackManager::TimeMarchesOn()
   nsISupports* parentObject =
     mMediaElement->OwnerDoc()->GetParentObject();
   if (NS_WARN_IF(!parentObject)) {
     return;
   }
   nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(parentObject);
 
   if (mMediaElement &&
-      (!(mMediaElement->GetPlayedOrSeeked())|| mMediaElement->Seeking())) {
+      (!(mMediaElement->GetPlayedOrSeeked()) || mMediaElement->Seeking())) {
     return;
   }
 
   // Step 3.
   double currentPlaybackTime = mMediaElement->CurrentTime();
   bool hasNormalPlayback = !mHasSeeked;
   mHasSeeked = false;
 
@@ -706,12 +702,15 @@ TextTrackManager::TimeMarchesOn()
       if (trackElement) {
         trackElement->DispatchTrackRunnable(NS_LITERAL_STRING("cuechange"));
       }
     }
   }
 
   mLastTimeMarchesOnCalled = currentPlaybackTime;
   mLastActiveCues = currentCues;
+
+  // Step 18.
+  UpdateCueDisplay();
 }
 
 } // namespace dom
 } // namespace mozilla

--- a/dom/html/TextTrackManager.h
+++ b/dom/html/TextTrackManager.h
@@ -78,38 +78,38 @@ public:
    * This takes the form of <foo.class.subclass>. These classes are then parsed
    * and set as the anonymous content's class attribute.
    *
    * Rules on constructing DOM objects from WebVTT nodes can be found here
    * http://dev.w3.org/html5/webvtt/#webvtt-cue-text-dom-construction-rules.
    * Current rules are taken from revision on April 15, 2013.
    */
 
-  /**
-   * Converts the TextTrackCue's cuetext into a tree of DOM objects and attaches
-   * it to a div on it's owning TrackElement's MediaElement's caption overlay.
-   */
-  void UpdateCueDisplay();
-
   void PopulatePendingList();
 
   void AddListeners();
 
   // The HTMLMediaElement that this TextTrackManager manages the TextTracks of.
   RefPtr<HTMLMediaElement> mMediaElement;
 
   void DispatchTimeMarchesOn();
+  void TimeMarchesOn();
 
   void NotifyShutdown()
   {
     mShutdown = true;
   }
 
 private:
-  void TimeMarchesOn();
+  /**
+   * Converts the TextTrackCue's cuetext into a tree of DOM objects
+   * and attaches it to a div on its owning TrackElement's
+   * MediaElement's caption overlay.
+   */
+  void UpdateCueDisplay();
 
   // List of the TextTrackManager's owning HTMLMediaElement's TextTracks.
   RefPtr<TextTrackList> mTextTracks;
   // List of text track objects awaiting loading.
   RefPtr<TextTrackList> mPendingTextTracks;
   // List of newly introduced Text Track cues.
 
   // Contain all cues for a MediaElement.