Till 9.x, the headers were under the resources in the Developer Tools, but now I can\'t find it anywhere.
For me, as of Google Chrome Version 46.0.2490.71 m, the Headers info area is a little hidden. To access:
While the browser is open, press F12 to access Web Developer tools
When opened, click the "Network" option
Initially, it is possible the page data is not present/up to date. Refresh the page if necessary
Observe the page information appears in the listing. (Also, make sure "All" is selected next to the "Hide data URLs" checkbox)
see screenshot