Examine source code of Password Strength Checker

{
  "manifest_version": 2,
  "name": "Password Strength Checker",
  "version": "1.0",
  "description": "that is going to be responsible for checking the strength of a password for the user’s understanding of their password strength by considering the length of the password which will be that the password should contain at least 8 characters and the other is that the password should contain one uppercase letter, one lowercase letter, one number and one special character.",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/stre-logo.png"
    }
  },
  "icons": {
    "128": "images/stre-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3ee46d14-3442-480e-b9bc-9837627e7bb7}"
    }
  }
}