how to avoid previous conversation chat window in google plus

My question is how to avoid the previous conversation of the chat in google plus because whenever I logout the google plus and when login I always see the chat window popup of the previous chat done. I want to know how can I avoid the previous chat window.

According to me whenever you try to chat with your friends and when you log out and login again you see that there are previous chats appeared on the screen. In this case I can suggest that you just clear out the chat with the friends and before logging out just see that you close the chat list or chat window of the your which you were chatting on because I was facing with the same problem and closing of the chat window have solved out the issue . just try with yours if still problem persist then there is always google for help.

Thanks for the helping me out I tried out this and have solve the issue.