Floating window always on top of main Window

I've updated to 2017.3 from 2017.1 on macOS and noticed that any floating window (undocked Asset Store, Custom Editor Window, etc) now appears in front even when the main window is in focus, and this wasn't always the case. I cannot find a setting for it; is this the new behavior? I see it happening in the 2018 beta as well. Any way to change it back? (Other than going back to 2017.1, which works) Thanks!

 

same here.. any workaround?

 

There seems to be a report for it: https://issuetracker.unity3d.com/issues/cannot-toggle-between-two-unity-windows
Just bumped into this when upgrading to 2017.3.1f1.