Is "id" property given by figma.currentUser unique for a user?

As explained here: [User | Plugin API](https://User - id), the “id” property would either be a value or null.

Question 1: Can a user open and use a plugin without signing up an account on Figma?
Question 2: Would this set value for “id” be unique for all users and would it be consistent/same on both Figma’s Website and Desktop app for a particular user?

Thanks!

  1. No
  2. Yes