Almost a 5 star extension, if it worked the way it ought to.

Expected: A hot-key, like CTRL+F11 to toggle hide/show of browser UI elements in the current tab.

Actual: 1. Disable extension; 2. Open a new window with the desired website. 3. Open Manage Extensions page; 4. Enable extension -- the first tab will now pop out into an undecorated window. 5. Disable extension.

I sooooo wish it worked properly, as I frequently want to reduce a tab to an absolutely minimal UI.