Examine source code of Rooster Reader for LINGQ

{
  "manifest_version": 2,
  "name": "Rooster Reader for LINGQ",
  "description": "GUI Overlay for LINGQ listen mode.",
  "version": "1.392",
  "content_scripts": [
    {
      "matches": [
        "https://www.lingq.com/*/learn/*/web/*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "permissions": [
    "https://www.lingq.com/*"
  ],
  "host_permissions": [
    "https://www.lingq.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1c653da5-c068-4f50-a251-66d02381203b}"
    }
  }
}