Examine source code of yourbang

{
  "name": "yourbang",
  "version": "1.1.1",
  "description": "Your own !bang search, just like Duckduckgo but you can define your own bangs.\n\nHow to use: ! <keyword> <item>\n\nExamples: ! google test",
  "author": "Outvi V",
  "background": {
    "scripts": [
      "bg.js"
    ]
  },
  "omnibox": {
    "keyword": "!"
  },
  "permissions": [
    "tabs",
    "storage"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "content_security_policy": "script-src 'self'; object-src 'self';",
  "manifest_version": 2,
  "icons": {
    "48": "icon-48.png",
    "96": "icon-96.png"
  },
  "homepage_url": "https://github.com/outloudvi/yourbang/"
}