UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.139 Safari/537.36

Steps to reproduce the problem:
- Go to any web page (www.google.com for example)
- Hit F12 to Open the developer Tools
- Hit F12 again

What is the expected behavior?
Previous behavior before 66.x was the hitting F12 a second time would close the tools

What went wrong?
Current behavior now toggles between the developer tools and the web page itself

Did this work before? Yes < 66.x

Chrome version: 66.0.3359.139  Channel: stable
OS Version: 10.0
Flash Version: 

It would be nice to have this functionality back (or OPT-IN) since if Chrome is taking a moment to close the developer window (long AJAX call, busy workstation, etc), it leads to accidental double clicking of the close button. 

The second click, ends up closing the application behind chrome's developer window when this occurs.