Text message pop up notification

[eric002]

Well, just as my title suggests, I understand me Google messenger app because apparently MMS capabilities are great at all with the application. I went back to the stock Android messaging application the one with the green icon. It was great MMS messages were perfect. The one thing I do not understand, is the pop-up notification that we see in the top and lollipop doesn't work very well with this application. Does anyone know why?

32 gig custom made 2nd gen Moto X by moto maker running lollipop 5.0