Examine source code of Latest Tweets First

{
  "icons": {
    "128": "src/icon.png"
  },
  "browser_action": {
    "default_icon": {
      "128": "src/icon.png"
    }
  },
  "content_scripts": [
    {
      "js": [
        "./src/content.js"
      ],
      "matches": [
        "https://www.twitter.com/*",
        "https://twitter.com/*"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "background": {
    "scripts": [
      "./src/background.js"
    ]
  },
  "description": "Always show latest tweets with the new Twitter Layout.",
  "manifest_version": 2,
  "name": "Latest Tweets First",
  "short_name": "Latest Tweets First",
  "permissions": [],
  "version": "1.1"
}