Examine source code of Tab Wrangler

{
  "manifest_version": 2,
  "name": "Tab Wrangler",
  "version": "0.14resigned1",
  "description": "Wrangle your tabs!",
  "permissions": [
    "contextMenus",
    "tabs"
  ],
  "applications": {
    "gecko": {
      "id": "{f82cbc08-ccb2-4adb-b2ec-f72310650602}",
      "strict_min_version": "42.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "96": "icons/icon.png"
  }
}