I just opened Stars and PT4 at the same time. I got the pop up to upgrade PT4 to 4.08.3 but clicked ok to skip it, since it's not important for me atm.
While things were loading there was a "downloading files 1 of 2" type of popup that quickly came and went.
If this was PT4 downloading some essential files or something that's fine with me. I just have no idea where it was from. Stars didn't pop up with the click ok to update to a new version like they normally do. So I'm just wondering what that was. I had chrome open as well as a windows photo viewer. So if it wasn't PT4 or Stars, it's scary.