I just updated google-chrome-stable to version 32.0.1700.77 in my Ubuntu 13.04.
I tried to use this renamed feature, now called screen emulation, so I set the resolution to different values, but all I got was this message:
screen emulation is not available on this page
I can't confirm if is it working for other OS/Chrome versions setup, but I'm pretty sure that it may be a problem with Google Chrome for Linux. Also I can't find discussion, blog post or even Chrome changelog.
Is it a bug or is it something in Ubuntu?
On chrome://flags I enabled the "Override software rendering list" option, which solved the issue.
Chrome 34.0.1847.116 chrome://flags "Override software rendering list" didn't work for me, I've had to disable "GPU compositing on all pages"
I had the same issue on ubuntu 12.04. But enabling "Override software rendering list" option did not work for me. I checked current chrome version
Version 32.0.1700.102
and then I updated chrome toVersion 32.0.1700.107
and it started working.