Examine source code of Focus Scroll Limit

{
  "manifest_version": 2,
  "name": "Focus Scroll Limit",
  "description": "Limit page scroll between two CSS selectors or specific pixel offsets",
  "version": "1.1",
  "icons": {
    "64": "icons/icon64.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/icon64.png",
    "default_title": "Focus Scroll Limit",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e25cb9df-5d9f-4096-9016-973e1ebf5f6f}",
      "strict_min_version": "90.0"
    }
  }
}