Great suggestion! Unfortunately I am not very familiar with Docker/Portainer yet and therefore a bit afraid of messing things up with my Home Assistant installation doing things I am not 100% sure of. I will go for the request!
Have a look at this thread How to modify mosquitto.conf? - #4 by 123 - particularly the last post. I think this is how I permanently changed the log file date format for mosquitto - though it was a while ago, so I hope things haven’t changed.
I created the file /share/mosquitto/mosquitto.conf and put the configuration content in it (from your linked post). After that, I restarted the Mosquitto Add-in.
Here is the log output:
I’m absolutely not an expert, but my Add-in seemed to expect another config, /etc/mosquitto.conf ?
The strange thing is that when I tried to reach that file from VS Code Add-in, /etc/mosquitto.conf wasn’t there. I guess there is something I do not fully understand here?