Widget background does not cover the whole widget area

When assigning a background to a widget, the widget/background does not cover the whole area of the widget.

  1. Create a new widget and resize it to be as large as possible.
  2. Assign a solid background to the Root.

In this case this is seen this is seen when using Nova Launcher without any paddings and a widget covering the whole screen. What I'm doing is using a KWGT widget as background for multiple other widgets which do not come with a matching background. I'm creating a new widget, assing a background color and push it in the background of the other widgets.

However, there are a few pixels as padding on the sides of the widgets which are not covered by the set background color.