If you zoom in on the image all the way with the controls (to load the highest detail tiles), and then zoom your browser window out all the way, the full-detail

If you zoom in on the image all the way with the controls (to load the highest detail tiles), and then zoom your browser window out all the way, the full-detail image will be rendered at full size and can be saved by right-clicking the canvas and asking to view the image in a new window, then saving that image. I’m currently enjoying a beautiful new desktop background :)