The EMQ X 3.0-rc.1 release is mainly for bug fixes and new feature improvements on MQTT 5.0.

EMQ X Core

Enhancements:

• Add request & response support for CONNECT & CONNACK GitHub PR: emqx/emqx#1819

• Add warning logs for unauthorized subscribe Github PR: emqx/emqx#1878

• Improve coverage for emqx_hooks, and add test case for emqx_mod_sup Github PR: emqx/emqx#1892

Bug Fixes:

• Fix the bad link to ACL doc Github PR: emqx/emqx#1899

• Fix bug in validating publish packet Github PR: emqx/emqx#1888

• Fix bugs that not deliver Reason Code to client Github PR: emqx/emqx#1819

• Fix compatibility problems in emqx_client module Github PR: emqx/emqx#1819

emqx-lwm2m

• Update LwM2M plugin for EMQ X 3.0 Github PR: emqx/emqx-lwm2m#3