The HIG advises against document-level tabs in an app, largely because at the time, the usability team hoped GNOME would have a tabbed window manager in its not-too-distant future. The tab-related activity in the past week has me thinking me that we need this more than ever! App developers shouldn’t have to implement basic window management features, and (perhaps more importantly) users shouldn’t be restricted to grouping documents from the same application into tabbed windows–with a tabbed WM, they could still do so if they wanted to of course, but they’d also be free to group windows by task or project, or indeed any other way they wanted.

Is it worth starting to think a bit harder about how a tabbed WM might work (I don’t think we’ve ever sat down to try to design one for GNOME, although I know at least one tabbed WM has been implemented before)?  Or is it just something that’s just never likely to happen?