I/O tracks in arranger view - How'd I do that?

I noticed that in my arranger window appeared folder track with all input/output tracks in it. I have no idea how it got there. I must have pressed something. But it could come handy, in case I need it.

How do I put it there, when I need it? Is there a shortcut, that puts it there? Or some command?
Who knows, pls let me know.

Turn on write automation for that track and it will appear in the project window.

Yes, thats it. Thnx.

Actually I clicked “Toogle Write for all tracks”, and all i/o tracks appeared in project window. Useful.