Ha, I was going to say that this is possibly not possible, before I tried this:
browser.window.move_to(-1200,0)
My second monitor is oriented to the left of my main screen. It worked. Good question.
You will need to fool it in order to get everything right, but it looks like it can use the entire canvas of monitors. If your monitor was taller than your main screen, for example, you move it there using something like
browser.window.move_to(0,-1000)
boulder_ruby
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