Examine source code of Duolingo Discord

{
  "manifest_version": 2,
  "name": "Duolingo Discord",
  "version": "1.0",
  "description": "Add flags and other visual cues to Duolingo Discord navigation sidebar.",
  "author": "Cory der Große",
  "homepage_url": "https://corydergrosse.github.io",
  "icons": {
    "16": "icons/icon_16.png",
    "48": "icons/icon_48.png",
    "96": "icons/icon_96.png",
    "128": "icons/icon_128.png"
  },
  "web_accessible_resources": [
    "img/*.png"
  ],
  "content_scripts": [
    {
      "css": [
        "style.css"
      ],
      "js": [
        "content_firefox.js"
      ],
      "matches": [
        "https://discord.com/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{bd70a38b-2f70-4be2-8ebf-71c5e1e0bb8f}"
    }
  }
}