Examine source code of Text Highlighter v1

{
  "manifest_version": 2,
  "name": "Text Highlighter",
  "version": "1.0",
  "description": "Highlight text on a webpage and display it in a popup.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": [
      "popup.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f4635c4b-32d7-4baf-8a0d-6f22efe8f089}"
    }
  }
}