Validate Certificate vs. Encryption (tls)

[SunSDSE]

First, I love what you have done. It's a far better application than the tool I created for myself six years ago.

I have MQTT running within my Docker Swarm using LetsEncrypt certificates.
https://hub.docker.com/_/eclipse-mosquitto

Currently, I use two apps, one on my iPhone and the MQTT-Explorer.
The iPhone Application; MQTTInspector will connect using TLS/8883 and see the traffic. When the certificate is expired it will not connect.

I am not sure if the issue is with the LetsEncrypt certificates or something else.
The MQTT-Explorer with the Encryption toggle on, and Validate Certificate toggle on, reports the "certificate has expired"
Feel free to check it out at cyva.lese-fowler.us using port 1883 or 8883

If we turn off the Validate certificate toggle the MTT Explorer will see the traffic.
This is great, however, I think it would be better if you could have a way to show us the certificate that is presented. Similar to when in a browser and you click on the HTTPS lock it will show you the certificate that is presented.

There are times when my LetsEncrypt certificate did not update correctly and having your application show the certificate that it sees, would be a quick way of knowing the certificate is old.

[joaodforce]

I have the same issue, this is probably because of the old electron build that MQTT-Explorer is using, it has an old cert trust chain baked in which is causing this issue.