Examine source code of Sea Tab

{
  "manifest_version": 2,
  "name": "Sea Tab",
  "description": "Open a tab, clean the ocean",
  "version": "1.0.0.2",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_action": {
    "default_icon": "./images/icon.png"
  },
  "icons": {
    "16": "./images/icon16.png",
    "32": "./images/icon32.png",
    "48": "./images/icon48.png",
    "128": "./images/icon128.png"
  },
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}