Symfony + Mercure connection problems. Use HTTPS instead of HTTP
Okey I found it. If anyone has the same problem add SERVER_NAME variable to your docker-compose configuration. Mercure use Caddy server which is set by default to force HTTPS.
mercure: image: dunglas/mercure environment: MERCURE_PUBLISHER_JWT_KEY: '!ChangeMe!' MERCURE_SUBSCRIBER_JWT_KEY: '!ChangeMe!' SERVER_NAME: ":80"