Examine source code of Text Highlighter

{
  "manifest_version": 2,
  "name": "Text Highlighter",
  "version": "1.0",
  "description": "Highlight selected text on a webpage.",
  "permissions": [
    "activeTab",
    "contextMenus",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{357a55aa-46fe-4f90-a391-4f6736a76c75}"
    }
  }
}