UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.59 Safari/537.36

Steps to reproduce the problem:
1. Open devtools.
2. Start to drag "Source" tab label.

What is the expected behavior?
"Source" panel should be detached from current place, become as floating window, and drag'n'drop should be initialized.

What went wrong?
We have no possibility to align two (or more) panels at same time side-by-side: f.e. "Elements" tab and "Source"tab. 
(see attached image)
In case we have a big (4k) monitor it would be great to have possibility to see at once:
 - Result page (which can behave as other tabs of devTools)
 - Elements tab
 - Source tab (possibility to see two files: f.e. html and css);

Did this work before? N/A 

Chrome version: 54.0.2840.59  Channel: n/a
OS Version: 
Flash Version: Shockwave Flash 23.0 r0
 

Deleted: Screenshot from 2016-10-21 14:44:10.png 913 KB

	Screenshot from 2016-10-21 14:44:10.png 913 KB View Download