Examine source code of Synonym Search

{
  "manifest_version": 2,
  "name": "Synonym Search",
  "version": "1.1resigned1",
  "description": "Search synonyms for selected text using thesaurus.com",
  "icons": {
    "48": "icons/sysearch-icon.png",
    "96": "icons/sysearch-icon.png"
  },
  "background": {
    "scripts": [
      "search-synonyms.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{30cbaa80-18ad-44fa-a6c7-f206fe691866}"
    }
  }
}