Document how to use plugin metrics, and how to extend [Besu metrics](../../public-networks/how-to/monitor/metrics.md) – for example, using a [validator monitoring plugin](https://github.com/Consensys/doc.quorumplugins/blob/master/docs/HowTo/Configure/Besu-Plugins/Monitor-Validators.md). This topic should go under **Plugins > How to** (see #1560).