HOW to create Multiple windows?

I can check float windows, and I understand Tile...but I just updated from PSE6 (yeah, I know...) and I miss the way you could have two windows open with two images and each had its own set of tools. That is, it was like having two complete windows open at the same time- with each image having its layers visible.  All I can do is click from one image to the other to make either active but  the tools and layers visible are ONLY for the currently active window.

What if I want to compare layers?

I really miss PSE6, and I'm doing everything I can not to go back:)