Examine source code of File form filler

{
  "name": "File form filler",
  "version": "3.1.0",
  "description": "Extension to form filling by uploaded excel or csv file",
  "permissions": [
    "tabs",
    "http://*/*",
    "https://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/fillFormsSimple.js",
        "js/fillMultipleForms.js",
        "js/generateFile.js",
        "js/fillWithGeneratedFile.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "128": "assets/images/iconOnly.png"
    }
  },
  "manifest_version": 2,
  "icons": {
    "128": "assets/images/iconOnly.png"
  },
  "web_accessible_resources": [
    "assets/images/iconOnly.png",
    "popup.html",
    "js/fillFormsSimple.js",
    "js/fillMultipleForms.js",
    "js/generateFile.js",
    "js/fillWithGeneratedFile.js"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{bc4d6850-45bc-4a98-95ee-45a88e7dfd63}"
    }
  }
}