Further investigation shows that the view does resize, but the drawing bounds are not updated, so that it never draws outside of the previous size. You can show this by using the arrow keys to scroll to the side where the white is, and see it temporarily update.
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Further investigation shows that the view does resize, but the drawing bounds are not updated, so that it never draws outside of the previous size. You can show this by using the arrow keys to scroll to the side where the white is, and see it temporarily update.