I binded this key to alt+O since its not used for anything, also, because ctrl+O is commonly used to "open" files.
i press alt+O with right hand fairly easily\
Also, I bind all my PDF manuals here. I prefer to view my long developer PDF documents locally since it loads faster when I scroll through pages, then opening a file on file attachment in dynalist or viewed in chrome, etc
so this comes in handy here