It'd be neat to have a "container window" within which you could put arbitrary applications in, and have a tab associated with each of them.

So you could group a bunch of open web pages, a word document and a file folder for some research on a particular topic. Or a game and a walkthrough together. Your repl, ide, and a web browser open on stackoverflow for some programming.

Instead of application-oriented navigation, you'd have group s of tasks that you'd navigate between. You'd probably ctrl-tab between tabs inside of a container more often than you'd alt-tab between tasks.