Examine source code of Base64 Encoder/Decoder

{
  "manifest_version": 2,
  "name": "Base64 Encoder/Decoder",
  "short_name": "Base64",
  "description": "Encodes and decodes media to and from Base64.",
  "version": "1.0.2.2resigned1",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Convert to and from Base 64"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d572677a-0d18-40ae-b465-8c1a237ebdd9}"
    }
  }
}