[Dark Vincent]

There is a code for it(I don't know it) but you'd have to make the image the exact size of the background and if they modify the window size then it may not look like you want it too.

For example if you have your board at a size to where it's best maximized then if they make the window smaller and you made the image fit the maximized size then it may look smaller, unless you're using 100% size then it will just make the image smaller with the window and make the image look a bit odd.