Gmail Unread Count Badge

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Gmail Unread Count Badge",
  "version": "2.0.1",
  "manifest_version": 3,
  "description": "Unread count badge for the Gmail icon",
  "homepage_url": "https://github.com/developit/gmail-app-badge-notification",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "host_permissions": [
    "*://*.mail.google.com/mail/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.mail.google.com/mail/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ]
}