I'm not sure I completely follow, aren't tabs still within the same window? How would tabs solve the 'keeping everything inside a single window' problem? Is th

I'm not sure I completely follow, aren't tabs still within the same window? How would tabs solve the 'keeping everything inside a single window' problem? Is the conversation list on the left side of the window not analogous to tabs? A conversation can be pinned there which would be providing the same experience as keeping a conversation open in a tab.