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		<Rectangle.Fill>
			<VisualBrush TileMode="FlipY" Viewport="0,0,0.5,0.5">
				<VisualBrush.Visual>
					<StackPanel Background="White">
						<TextBlock>Przykładowy tekst</TextBlock>
						<Button>OK</Button>
					</StackPanel>
				</VisualBrush.Visual>
			</VisualBrush>
		</Rectangle.Fill>
	</Rectangle>