1. I created a pinned tab to http://mail.google.com
2. Then I quit Chrome so it's not running.
3. I open up Chrome again and the pinned tab appears with Gmail as expected
4. WIth the login prompt on the page, I press cmd-\ shortcut key. It does not work at this point.
5. If I refresh the screen (I clicked on the address bar, and pressed enter), then the shortcut key works. I can also use the extension icon near the address bar just not the shortcut key. I tried it a few times, and it seems consistant for me.
Snow Leopard 10.6.6
1Password 3.5.1 build 30802