Opening ChatApplication in a Pop Up Window using JavaScript

I'm working on this project website wherein i will be adding a chat application where users can communicate with each other. I already have developed a chat room webpage which is now functioning well. However, what I want is to create a "Chat Room开发者_运维百科" link on my website which will just pop out the chat room as a pop-up window upon click.

Can somebody please help me on how to do this? Thanks everyone. :)

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If you link to the chat room has target = "_blank", it will open in a new window:

<a href="chatroom">opens inline</a>

<a href="chatroom" target="_blank">opens in a new window</a>

This is just normal HTML / browser behavior.