Event fires two mails instead of one when upgrading laravel framework

[grn-dk]

When executing the event: event(new Registered($user)); two email verification mails are sent when User model implements MustVerifyEmail upon user registration.

Any ideas how to debug this further? Our project is currently stuck at laravel/framework v11.8.0.

On versions above laravel/framework 11.8.0 with laravel breeze starter-kit. I am not able to reproduce on a vanilla Laravel Breeze.

Postgres 16.3
PHP 8.3.6
laravel/framework 11.9.0 -> 11.15.0