I'm running Ubuntu 12.04 64-bit and Google Chrome version 28.0.1500.71 (the latest as of this writing).
There are a lot of themes with transparency in the Chrome Web Store, but they never work on my system. What kind of configuration am I missing to make transparent themes work in Chrome?
Here is an example of a theme that should be transparent but is not:

On my system (the dark gray title-bar is not transparent):

From my about:gpu page (before enabling flags and messing with stuff):

about:gpu page (after messing with stuff)
