I started using Nostr and Alby quite some time ago. Then I had to reformat my computer. I am using Ubuntu OS and the Brave browser. Now when I log on to Iris.io it brings up a separate Alby window that says: “Set a passcode to unlock Alby Extension in this browser”. I don’t understand what that is. I do not remember seeing that prompt previously. Please clarify what I am supposed to do. Pretend that I am your grandmother in your explanation please. 

 This is a customer service question.