Pressing Ctrl-Shift-f when the extension content is focused doesn't close the sidebar

[jkakar]

It would be nice if this worked. I don't keep it open most of the
time, so my workflow is often:

1. Look at webpage and decide I want to comment/tag it.
2. Hit Ctrl-Shift-f to open the sidebar.
3. Enter my comment.
4. Hit Ctrl-Shift-f to close the sidebar... nothing happens, so I
   have to click in the page content area and then hit the keystroke
   again to make the sidebar go away.