If a I create a simple form with just a RadGridView control:
As I resize the window, the grid streches with the window and vertical/horizontal scrollbars appear if there's any extra rows/columns in the grid. But if I change the container to a canvas:
Then any overflow is hidden. Even if I wrap the RadGridView in it's own grid under the canvas no scrollbars appear. This seems to happen if there's a canvas element anywhere in the container hierarchy.