A melhor coisa que você pode fazer é acessá-lo na página "Aplicativos" usando o atalho do aplicativo na Barra de marcadores do Google Chrome para abrir o aplicativo.
To enable access to your apps page from the bookmarks bar, just right click on the the toolbar and make sure
Show apps shortcut
(red circle) has a check mark by it. Once this is done you'll see the Apps shortcut (green circle).
ToaddtheHangoutsApplicationtoyourdock,gototheAppspage.ThenrightclickontheHangoutsapplicationandselect
Createshortcuts...
This is where my screenshots won't come in handy because I'm on a Windows machine at the moment. Once you click the 'Create shortcuts...' a box will pop up saying something like Add to applications folder. Once you do that it will open up the Applications folder and you can then drag the Hangouts icon into your dock bar. This will give you easy access to be able to open the application without having to use your previous launch methods.
PS Eu adicionei o método dock porque pode haver a possibilidade de entrar em dois perfis de uma só vez e alternar facilmente. Eu não tenho certeza, porque eu nunca tentei.