--- a/dom/media/mediasource/MediaSourceDecoder.cpp
+++ b/dom/media/mediasource/MediaSourceDecoder.cpp
@@ -302,24 +302,30 @@ MediaSourceDecoder::NextFrameBufferedSta
 }
 
 bool
 MediaSourceDecoder::CanPlayThroughImpl()
 {
   MOZ_ASSERT(NS_IsMainThread());
   AbstractThread::AutoEnter context(AbstractMainThread());
 
+  if (mEnded) {
+    // Return true for we have all the data.
+    return true;
+  }
+
   if (NextFrameBufferedStatus() == MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE) {
     return false;
   }
 
   if (IsNaN(mMediaSource->Duration())) {
     // Don't have any data yet.
     return false;
   }
+
   TimeUnit duration = TimeUnit::FromSeconds(mMediaSource->Duration());
   auto currentPosition = CurrentPosition();
   if (duration.IsInfinite()) {
     // We can't make an informed decision and just assume that it's a live
     // stream
     return true;
   } else if (duration <= currentPosition) {
     return true;