Examine source code of GitHub Activity Extension

{
  "manifest_version": 2,
  "name": "github-activity-extension",
  "author": "Darcy Clarke <darcy@darcyclarke.me>",
  "description": "Toggle display of noisy activity notifications in issue & PR threads ",
  "version": "1.0.3",
  "homepage_url": "https://github.com/darcyclarke/github-activity-extension",
  "incognito": "spanning",
  "background": {
    "scripts": [
      "app.js"
    ]
  },
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "browser_action": {
    "default_icon": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://github.com/*"
      ],
      "run_at": "document_end",
      "js": [
        "inject.js"
      ]
    }
  ],
  "permissions": [
    "activeTab",
    "storage"
  ]
}