Comment by Twey
16 hours ago
There's nothing stopping a window manager from supporting docking windows to each other, or the more common option in tiling window managers of having nested tiling groups so you can arrange your editor windows however you like and manipulate them together. Metisse [1] takes it even further, letting you slice a ‘palette’ out of one window and put it in another. In practice I, like you and I suspect a lot of other people, use workspaces in lieu of task groups, which works fine for simple use cases and small monitors.
The only applications that really need MDI are those that do something with their windows other than window management, which (loosely) implies that those things are something other than windows.
There is a lot of stuff that window managers could in theory do (e.g. something i'd like Window Maker to be able to do is "combining" windows so that the title bar becomes a tab bar that contains multiple windows in the same screen space region) but in practice never end up doing for whatever reasons (i could in theory spend the time to implement such a feature in Window Maker but it is very low in my priorities for whenever i have time to spend). And more importantly, not everyone has the same window manager, so even if my window manager could provide a feature that made some application feature unnecessary, someone else's window manager might still not provide it (but might provide some other feature they want that mine doesn't).
> The only applications that really need MDI are those that do something with their windows other than window management, which (loosely) implies that those things are something other than windows.
Well, in the example of image editors i mentioned, these windows are views to the underlying image documents - and being able to move and resize those views arbitrarily, together with a caption about the document they're about, is very useful. It also matches perfectly with embedded/MDI windows.