Examine source code of Reader View Plus

{
  "manifest_version": 2,
  "name": "Reader View Plus",
  "version": "1.0.0",
  "description": "Simple Reader View enhancements: extract main article, adjustable font size, line height, toggle dark mode, and print/export the cleaned article.",
  "permissions": [
    "activeTab",
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Reader View Plus",
    "default_popup": "popup/popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_scripts/reader.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "web_accessible_resources": [
    "content_styles/reader.css"
  ],
  "applications": {
    "gecko": {
      "id": "readerviewplus@example.com",
      "strict_min_version": "60.0"
    }
  }
}