Generating a new session from same browser

I would like to open another instance of a yii web app with the same browser, but it appears that all the yii::app states are passed to the new browser window and the sessionid is the same. How is another "clean" instance of a web app opened with yii??

Browsers do what they are expected to do and send back session cookie even if you open a new tab or window. What do you want to achieve? Separate sessions for different parts of site (eg. backend and frontend sessions) or open the same page in the same browser but as a new user? The former can be handled on server side by configuring session cookie and restricting it by subpath or subdomain. The latter depends on the browser and usually isn’t trivial. Browser plugins like this one can help.

Thanks, the browser plugin is what I needed.