I switched to a different user and got logged out. Can I not view two users at the same time?

You can open as many windows/tabs as you want, but you must open them from an existing session in order to remain logged in.

To do this:
1. Right click on a link in the system, for example the Dashboard link in the menu bar. 2. Select Open in New Window, or Open in New Tab. 3. You can navigate around in either window/tab without issue. Logging out of either one will end the session for both.

If you instead open a fresh window and navigate to your site it will log you out. This is because the creation of the new session destroys the old session.