RabbitMQ `3.9.28` is a maintenance release in the `3.9.x` release series.
This series [**reaches end of general support** on Jan 31st, 2023](https://rabbitmq.com/versions.html).
Please refer to the **Upgrading to 3.9** section from [v3.9.0 release notes](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.9.0)
if upgrading from a version prior to 3.9.0.
This release requires at least Erlang 24.3, and supports Erlang 25.
[RabbitMQ and Erlang/OTP Compatibility Matrix](https://www.rabbitmq.com/which-erlang.html) has more details on Erlang version requirements for RabbitMQ.
### Minimum Supported Erlang Version
Erlang 23 support has reached its [end of support](https://www.rabbitmq.com/which-erlang.html).
Starting with this release, RabbitMQ requires Erlang 24.3 or later versions. Nodes **will fail to start** on older Erlang releases.
## Changes Worth Mentioning
Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://github.com/rabbitmq/rabbitmq-server/tree/v3.9.x/release-notes).
### Core Server
#### Enhancements
* Preserve additional information in the log message when heartbeat frame cannot