Examine source code of Readable Font Size

{
  "content_scripts": [
    {
      "js": [
        "content-persistent.js"
      ],
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_start"
    }
  ],
  "description": "alf + f to get good font size",
  "icons": {
    "16": "images/icon_16.png",
    "48": "images/icon_48.png",
    "128": "images/icon_128.png"
  },
  "manifest_version": 2,
  "name": "Readable Font Size",
  "version": "1.0.3resigned1",
  "browser_specific_settings": {
    "gecko": {
      "id": "{292ef7e7-cf6a-4da2-8ff8-cc4398e9dc16}"
    }
  }
}