Tasmota on Sonoff POW R2 and MQTT over TLS with a Mosquitto broker

[Noklm]

Hello,
Firstly I've scoured the issues for this problem but haven't found the solution. The closest issue to my problem #11378

Context:
I have a Mosquitto MQTT broker with port 8883 open and TLS certificates automatically provided by caddy, see my mosquitto conf below:

listener 8883 0.0.0.0
certfile /mosquitto/certificates/caddy/certificates/acme-v02.api.letsencrypt.org-directory/mqtt.domain.com/mqtt.domain.com.crt
keyfile /mosquitto/certificates/caddy/certificates/acme-v02.api.letsencrypt.org-directory/mqtt.domain.com/mqtt.domain.com.key
cafile /etc/ssl/certs/ca-certificates.crt
tls_version tlsv1.2

To be clear my broker works like a charm.

I followed instructions on how to build tasmota 14.2.0 with MQTT TLS enabled and see below my_user_config.h:

#ifndef USE_MQTT_TLS 
#define USE_MQTT_TLS 
#define MQTT_TLS_ENABLED       true             // [SetOption103] Enable TLS mode (requires TLS version)
#define USE_MQTT_TLS_CA_CERT
#define USE_MQTT_TLS_FORCE_EC_CIPHER
#endif

I also tried USE_MQTT_TLS_CA_CERT even that is deprecated but
I compiled and flash my sonoff pow r2 without any problem.

The tasmota console logs, 296 - SSL3_ALERT_HANDSHAKE_FAILURE:

17:23:36.536 MQT: TLS connection error: 296
17:23:36.537 MQT: Connect failed to mqtt.domain.com:8883, rc -2. Retry in 10 sec

My broker logs:

1728404649: OpenSSL Error[0]: error:140260C1:SSL routines:ACCEPT_SR_CLNT_HELLO:no shared cipher
1728404649: Client <unknown> disconnected: Protocol error.

The problem seems to come from cipher, so I tried some desperate conf on caddy and mosquitto but without success, see the public key info of broker below:

$ openssl s_client -tls1_2 -connect mqtt.domain.com:8883
New, TLSv1.2, Cipher is ECDHE-ECDSA-AES256-GCM-SHA384
Server public key is 256 bit

Does anyone have any ideas to help me? I simply want to connect my sonoff pow R2 to my MQTT mosquitto broker over TLS.

Thank you in advance.