Sort of this! Basically I meant that I have about four windows in two different browsers open at any given time, so I had it open in a tab in the browser window where "stuff related to projects I am theoretically but not actively working on" goes. I just left off specifying that it was in a tab in the window, I guess. (The others are "daily messing around", "stuff related to projects I am actively working on" and "private window for websites I need a private window for".)

My browsers currently save your windows when closed/re-opened, so the windows get preserved just like the tabs when I restart, and thus I can stack a ludicrous number of windows just like I can stack a ludicrous number of tabs, but I guess some browsers still don't do that?