diff --git a/dom/media/mediacontrol/MediaControlService.cpp b/dom/media/mediacontrol/MediaControlService.cpp
index fe5e3e20f8ea..26cf0caa14f8 100644
--- a/dom/media/mediacontrol/MediaControlService.cpp
+++ b/dom/media/mediacontrol/MediaControlService.cpp
@@ -168,7 +168,7 @@ void MediaControlService::NotifyControllerPlaybackStateChanged(
   }
 }
 
-void MediaControlService::NotifyControllerBeingUsedInPictureInPictureMode(
+void MediaControlService::RequestUpdateMainController(
     MediaController* aController) {
   MOZ_DIAGNOSTIC_ASSERT(aController);
   MOZ_DIAGNOSTIC_ASSERT(
diff --git a/dom/media/mediacontrol/MediaControlService.h b/dom/media/mediacontrol/MediaControlService.h
index 6daa33487309..2ef639e7c244 100644
--- a/dom/media/mediacontrol/MediaControlService.h
+++ b/dom/media/mediacontrol/MediaControlService.h
@@ -51,10 +51,9 @@ class MediaControlService final : public nsIObserver {
   // This method would be called when the controller changes its playback state.
   void NotifyControllerPlaybackStateChanged(MediaController* aController);
 
-  // This method would be called when the controller starts to being used in the
-  // picture-in-picture mode.
-  void NotifyControllerBeingUsedInPictureInPictureMode(
-      MediaController* aController);
+  // This method is used to help a media controller become a main controller, if
+  // it fits the requirement.
+  void RequestUpdateMainController(MediaController* aController);
 
   // The main controller is the controller which can receive the media control
   // key events and would show its metadata to virtual controller interface.
diff --git a/dom/media/mediacontrol/MediaController.cpp b/dom/media/mediacontrol/MediaController.cpp
index 3108bebc55d2..6bc88eba8ca4 100644
--- a/dom/media/mediacontrol/MediaController.cpp
+++ b/dom/media/mediacontrol/MediaController.cpp
@@ -344,7 +344,7 @@ void MediaController::SetIsInPictureInPictureMode(
   UpdateActivatedStateIfNeeded();
   if (RefPtr<MediaControlService> service = MediaControlService::GetService();
       service && mIsInPictureInPictureMode) {
-    service->NotifyControllerBeingUsedInPictureInPictureMode(this);
+    service->RequestUpdateMainController(this);
   }
   UpdateDeactivationTimerIfNeeded();
   mPictureInPictureModeChangedEvent.Notify(mIsInPictureInPictureMode);
@@ -358,6 +358,10 @@ void MediaController::NotifyMediaFullScreenState(uint64_t aBrowsingContextId,
   LOG("%s fullscreen", aIsInFullScreen ? "Entered" : "Left");
   mIsInFullScreenMode = aIsInFullScreen;
   UpdateActivatedStateIfNeeded();
+  if (RefPtr<MediaControlService> service = MediaControlService::GetService();
+      service && mIsInFullScreenMode) {
+    service->RequestUpdateMainController(this);
+  }
   mFullScreenChangedEvent.Notify(mIsInFullScreenMode);
 }