--- a/dom/media/MediaRecorder.cpp
+++ b/dom/media/MediaRecorder.cpp
@@ -555,30 +555,34 @@ public:
     LOG(LogLevel::Debug, ("Session.Pause"));
     MOZ_ASSERT(NS_IsMainThread());
 
     NS_ENSURE_TRUE(mTrackUnionStream, NS_ERROR_FAILURE);
     mTrackUnionStream->Suspend();
     if (mEncoder) {
       mEncoder->Suspend();
     }
+    NS_DispatchToMainThread(
+      new DispatchEventRunnable(this, NS_LITERAL_STRING("pause")));
 
     return NS_OK;
   }
 
   nsresult Resume()
   {
     LOG(LogLevel::Debug, ("Session.Resume"));
     MOZ_ASSERT(NS_IsMainThread());
 
     NS_ENSURE_TRUE(mTrackUnionStream, NS_ERROR_FAILURE);
     if (mEncoder) {
       mEncoder->Resume();
     }
     mTrackUnionStream->Resume();
+    NS_DispatchToMainThread(
+      new DispatchEventRunnable(this, NS_LITERAL_STRING("resume")));
 
     return NS_OK;
   }
 
   nsresult RequestData()
   {
     LOG(LogLevel::Debug, ("Session.RequestData"));
     MOZ_ASSERT(NS_IsMainThread());