During the designs for the Translate extension, we thought on making the left toolbar disappear in some circumstances. Translators are very focused on the content and the links provided by the left side toolbar are rarely needed while translating.

The idea is to hide the toolbar initially to reduce the amount of chrome and provide a cue so that users interested in it can bring it back. I created an interactive prototype to illustrate the idea.

I like the idea, but I'm not sure there's a clear affordance for re-expanding the sidebar. My natural inclination was to click the small icon in the top-left, which does expand the sidebar but also takes me directly to the home page and leaves no way to get back to where I was.

Eventually I noticed what looks like a "configure" or "settings" icon, which appears to open the sidebar without navigating. Not sure this is ideal.

-- brion