Examine source code of Readerbear Importer

{
  "manifest_version": 3,
  "name": "Readerbear Importer",
  "version": "0.0.5",
  "description": "Import YouTube videos, Netflix shows, and articles into Readerbear to learn Japanese",
  "browser_specific_settings": {
    "gecko": {
      "id": "extension@readerbear.app",
      "data_collection_permissions": {
        "required": [
          "websiteContent"
        ]
      }
    }
  },
  "icons": {
    "128": "icon128.png"
  },
  "action": {
    "default_icon": "icon128.png",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "assets/background.js"
    ],
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "https://netflix.com/*",
        "https://*.netflix.com/*"
      ],
      "js": [
        "assets/netflix-bootstrap.js"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://readerbear.app/import*",
        "http://localhost/import*"
      ],
      "js": [
        "assets/receiver.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "activeTab",
    "scripting"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "assets/youtube.js"
      ],
      "matches": [
        "https://youtube.com/*",
        "https://*.youtube.com/*"
      ]
    },
    {
      "resources": [
        "assets/netflix.js"
      ],
      "matches": [
        "https://netflix.com/*",
        "https://*.netflix.com/*"
      ]
    }
  ]
}