UI Text does not display properly in scene view but it is fine in game view

I have created 3 UI text elements on the canvas and can see that they appear in game view. However, in scene view, not only they do not appear but weird black triangles appeared, see screenshot. I'm assuming those black triangles are the text 'Title', 'Subtitle' and 'Body' but would like to see the proper text displayed. I am using a custom font as shown in screenshot.