Examine source code of SHiFTLANDS

{
  "manifest_version": 2,
  "name": "SHiFTLANDS",
  "version": "2.1.2",
  "description": "Redeems all possible borderlands 2/3/GOTY/TPS SHiFT codes",
  "icons": {
    "48": "icons/border-48.png",
    "96": "icons/border-96.png"
  },
  "permissions": [
    "activeTab",
    "tabs",
    "<all_urls>",
    "cookies",
    "http://*/*",
    "https://*/*",
    "*://*/*",
    "storage",
    "tabHide",
    "webNavigation",
    "webRequest"
  ],
  "browser_action": {
    "default_icon": "icons/border-32.png",
    "default_title": "SHiFTLANDS",
    "default_popup": "popup/border_menu.html"
  },
  "background": {
    "scripts": [
      "background_scripts/background.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true,
    "open_in_tab": false
  }
}