V4.0.4 corrects frequency reporting for multi-frequency devices. If the field named "freq" is not present in the JSON packet, the value associated with the field name "freq1" is used, if present. If neither field is present, the frequency value is set to 0.0.
V4.0.3 corrects the assignment of username/password for sites that deploy the MQTT broker with username/password authentication. The edits are noted in comments as '4.0.3' and are in 'set_params()' in a small section of code that assigns args.username and args.password.
V4.0.2 was a minor update that removed Paho-MQTT callback V1 support and uses the V2 callback protocol instead. The next major release of Paho-MQTT will not support V1 callback protocol at all, and current Mac OSX (Tahoe) and Raspberry Pi OS (Trixie) distributions now both support V2 callbacks.
If you need to use V1 callback protocol because your OS doesn't offer the current Paho-MQTT release, invoke the prior version, rtl_watch.4.0.1. Check your Paho_MQTT version with check_paho_version.