Examine source code of Discord Native Emoji

{
  "manifest_version": 3,
  "browser_specific_settings": {
    "gecko": {
      "id": "@dc-native-emoji",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "name": "Discord Native Emoji",
  "version": "0.1",
  "description": "Replaces the twemoji renders on Discord with the system's native emojis.",
  "action": {
    "default_title": "Discord Native Emoji"
  },
  "permissions": [
    "scripting",
    "activeTab"
  ],
  "host_permissions": [
    "https://discord.com/*",
    "https://*.discord.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://discord.com/*",
        "https://*.discord.com/*"
      ],
      "js": [
        "content_script.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "icons": {
    "48": "icons/icon-48.png"
  }
}