Blueprint Widget Green background

I am having a small issue with a widget. It is 600x500 with several buttons and an image stretched as a background to the panel. When I have it added to viewport, it looks fine in the 600x500 area but the rest of the screen fills up with a solid green “panel”. Thoughts?

Update, the screen stays green even after all widgets are killed. Ending and restarting the game resets it but adding a widget brings back the green.

I figured out what was causing it but not sure why… I had F5 assigned to bring the widget up but when I assigned to another key, it works fine. What does F5 do by default?