Photoshop file windows get lost behind Photoshop application frame

I often work with multiple files that I need to see side by side and it's best to work with them undocked. The problem is I always end up loosing some of the file windows and they end up being behind the photoshop application frame - completely behind the photoshop application.

As sugested by others, I've tried turning off the application frame as work-around and as someone who often works between Illustrator and Photoshop at the same time, it's equally frustrating but for different reasons. With the application frame turned off, photoshop ends up on top of Illustrator and with no application frame you end up with your lllustrator work and tools (or whatever) in the background which is visually annoying but the main problem is you often end up clicking on the Illustrator tools accidentally instead of photoshop and then it flips out of the application you're trying to work in and completely breaks your workflow. I could never get used to this and it drove me crazy. 

Ultimately, I don't understand the purpose or any benefit whatsoever of having file windows dissapear behind the application frame. I'm not aware of any other application that does this or why after so many years this hasn't been corrected. Seems like it should be a simple fix.