Stepping through WaitForEndOfFrame when GameView isn't visible

Using that simple code:

 IEnumerator EOF () {
      yield return null; // wait one frame so that SceneView focuses
      yield return new WaitForEndOfFrame (); // steping will hang here unless you focus GameView again
      Debug.Log ("Got here!");
 }
 
 void OnGUI () {
     if (GUILayout.Button ("Test")) {
         Debug.Break ();
         StartCoroutine (EOF ());
     }
 }

Using default layout (where Scene and Game are tabbed, so you can't see both at the same time), if I hit Play from the SceneView, and hit the Test button, I'd get to a paused state of the game and my SceneView focused.

If I try to step though my coroutine, I never get passed yield return new WaitForEndOfFrame (); unless I switch to GameView again.

No matter how many times I hit Step, the game gets paused there. Even the profiler stops reporting (despite frames keep counting).

Is this a bug?