The 1.12.1 version of MQTTX for Mac was provided as a free download on our website. This free Mac application was originally designed by EMQ Technologies Co., Ltd. The application is included in Internet & Network Tools.
From the developer:
MQTTX is a simple and elegant MQTT 5.0 client tool. It offers a convenient solution to quickly test the connection of MQTT/TCP, MQTT/TLS, MQTT/WebSocket Publish / Subscribe functions, and other features. It offers support for CA, self-signed certificates, and single/two-way SSL authentication.
You may want to check out more Mac applications, such as Covenant Eyes, IPNetTunerX or Ping, which might be related to MQTTX.