It turns out that even though the Nexus 7 2013 version is 1920 x 1200, the Chrome browser reports its width as 600px wide, which explains why I don’t see the full menu. Bummer…
Weird. This resolved by itself. Perhaps it was cached.
I used the custom JS/CSS I found in another thread because I also wanted to make the content area wider and side bar narrower. Perfect.