If you close the popup window, you will be logged out of IRC.
You can also use a separate IRC client such as the Chatzilla extension for Firefox. The network is EFnet and channel is #Shartak - if you need a server, try irc.efnet.org. If you have configured IRC within the browser, you might be able to use this link: EFnet - #Shartak
You are not logged in. By default you will be connected with a random nickname, to change to something else wait until you're connected and then type: /nick NewName
You cannot have spaces in your nickname.
Open Java IRC client in a new window.