Examine source code of Surf

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "version": "0.4.35",
  "name": "Surf",
  "description": "Surf rewards you for your everyday browsing.",
  "permissions": [
    "tabs",
    "activeTab",
    "http://*/",
    "https://*/",
    "storage",
    "webNavigation",
    "alarms"
  ],
  "oauth2": {
    "client_id": "616868683921-bpok9c7arg30t4srldtu4n1trobchint.apps.googleusercontent.com",
    "scopes": [
      "profile",
      "email",
      "openid"
    ]
  },
  "icons": {
    "192": "logo192.png",
    "512": "logo512.png"
  },
  "browser_action": {
    "default_icon": "logo192.png",
    "default_popup": "index.html",
    "default_title": "Surf"
  },
  "background": {
    "scripts": [
      "./background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "js": [
        "./web-app-bus.js"
      ],
      "run_at": "document_start",
      "matches": [
        "http://localhost:3000/*",
        "https://app.joinsurf-staging.com/*",
        "https://app.joinsurf.com/*"
      ]
    },
    {
      "js": [
        "./marketing-site-bus.js"
      ],
      "run_at": "document_start",
      "matches": [
        "https://surf-ae5ea3.webflow.io/*",
        "https://joinsurf.com/*",
        "https://www.joinsurf.com/*"
      ]
    },
    {
      "js": [
        "./giveaways-site-bus.js"
      ],
      "run_at": "document_start",
      "matches": [
        "http://localhost.test:3000/*",
        "http://dashboard.localhost.test:3000/*",
        "https://giveaways.joinsurf-staging.com/*",
        "https://dashboard.giveaways.joinsurf-staging.com/*",
        "https://giveaways.joinsurf.com/*",
        "https://dashboard.giveaways.joinsurf.com/*"
      ]
    },
    {
      "js": [
        "./alerts-bus.js"
      ],
      "run_at": "document_start",
      "matches": [
        "https://*/*",
        "http://*/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{3cc10b60-0b8a-4022-9e84-85e5f9540758}"
    }
  }
}