I use Firefox mostly but need Chrome for only a few sites used for work, so I'm not too familiar with it. How do I open a new window instead of a new tab in Chrome? This needs to be a choice I make each time, not a permanent change. I found some Javascript solutions online, but I don't know how to use Javascript in Chrome.

Right now, I just opened a new instance of Chrome from the Start menu, but I think that probably uses much more memory, and Chrome is piggy enough.