Examine source code of Eagle

{
  "manifest_version": 2,
  "name": "Eagle",
  "short_name": "Eagle",
  "description": "To activate, type 'e' followed by space into the Omnibox. Then enter your term and press enter to submit.",
  "version": "0.2.7",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/lib/stopwords_res.js",
        "js/relevanttext.js",
        "js/content.js"
      ]
    }
  ],
  "permissions": [
    "unlimitedStorage",
    "<all_urls>",
    "storage",
    "tabs"
  ],
  "browser_action": {
    "default_icon": {
      "19": "assets/19.png",
      "38": "assets/38.png"
    },
    "default_popup": "assets/popup.html"
  },
  "icons": {
    "16": "assets/16.png",
    "48": "assets/48.png",
    "128": "assets/128.png"
  },
  "applications": {
    "gecko": {
      "id": "@eagle",
      "strict_min_version": "57.0"
    }
  },
  "omnibox": {
    "keyword": "e"
  },
  "options_ui": {
    "page": "assets/preferences.html",
    "browser_style": false
  },
  "background": {
    "scripts": [
      "js/blacklist2.js",
      "js/lib/chrono.min.js",
      "js/textprocessing.js",
      "js/queryparser.js",
      "js/background.js"
    ]
  }
}