Examine source code of discord tool box

{
  "manifest_version": 2,
  "name": "discord tool box",
  "version": "1.2",
  "description": "トークンの保存やコピー、ロードなどができるDiscordの多機能拡張機能です",
  "icons": {
    "16": "icon/discord-tool-box-16.png",
    "32": "icon/discord-tool-box-32.png",
    "48": "icon/discord-tool-box-48.png",
    "128": "icon/discord-tool-box-128.png"
  },
  "permissions": [
    "activeTab",
    "storage",
    "contextMenus",
    "*://*.discord.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.discord.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{017fc552-2127-4c98-9789-7e41e702f7ce}"
    }
  }
}