If you'd like to try the extension, the README has an overview. However, if you don't want to peruse the code before trusting the extension with your private key, you can create a test Keybase.io account and try it out with that.
If you'd like to try the extension, the README has an overview. However, if you don't want to peruse the code before trusting the extension with your private key, you can create a test Keybase.io account and try it out with that.