A few years ago I experimented with Zotero in my browser (Firefox), added a few items, then gave it up and went back to my old way of taking notes. But more recently I decided Zotero was very likely essential and downloaded the app, created an account, started taking notes. But now I have noticed the Old Z in my browser is still there but not growing, evolving as the New Z as an app. I don't know how to kill off the Old Z (login info unknown) without somehow endangering new Z. Halp!