Organize all tabs opened by extensions (especially during initial sync)

[MrGreenTea]

I had this happen right now when setting up a new Zen instance. It synced all my extensions (which is nice). Many of them open a new page/tab on first install for their initial setup. This was really disorienting, as I was trying to do something at the same time. Each new tab was immediately focused and took me away from what I was doing.

My proposal is:
Extension tabs should be grouped in some way, so I can go through them later. They should not be mixed with regular tabs/pages in my opinion, as they're more like settings than "real" web pages.

Here is a screenshot of how it looks in my browser right now: