Mailhog not receiving Discourse emails

Installation
1

Hello,

I’m setting up Discourse on my MacBook (M2) to try it out before hosting it elsewhere. I’ve cloned the repository and configured app.yml to use Mailhog:

env:
  LC_ALL: en_US.UTF-8
  LANG: en_US.UTF-8
  LANGUAGE: en_US.UTF-8

  DISCOURSE_HOSTNAME: 'localhost'
  DISCOURSE_DEVELOPER_EMAILS: 'luigi7up@gmail.com'

  DISCOURSE_SMTP_ADDRESS: localhost
  DISCOURSE_SMTP_PORT: 1025
  DISCOURSE_SMTP_USER_NAME: ''
  DISCOURSE_SMTP_PASSWORD: ''
  DISCOURSE_SMTP_ENABLE_START_TLS: false
  SMTP_URL: localhost
  DISCOURSE_SMTP_AUTHENTICATION: none

I start Discourse using the launcher and access it at localhost:80. Concurrently, I run Mailhog via Docker:

docker pull mailhog/mailhog
docker run -d -p 1025:1025 -p 8025:8025 mailhog/mailhog

Mailhog’s UI is accessible at localhost:8025, and testing with a Ruby script confirms emails are received by Mailhog:

Mail.defaults do
  delivery_method :smtp, address: "localhost", port: 1025
end

However, when I register on Discourse, no emails are sent. I’ve checked the Docker container logs without finding any relevant entries.

Any suggestions on resolving this issue?

Thank you!