Examine source code of CyrillicPolski

{
  "manifest_version": 2,
  "name": "RuskiPolski",
  "version": "1.0",
  "description": "Converts latin polish to cyrillic polish. Contains no additional functionality. To undo changes simply reload page",
  "icons": {
    "48": "icons/rupl-48.png",
    "96": "icons/rupl-96.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/rupl-32.png",
    "default_title": "Convert to Cyrillic"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}