While having the Monitoring Data Reader role is necessary for accessing monitoring data, installing or managing plugins requires additional permissions. Specifically, the managed identity associated with your Grafana workspace must have the "Grafana Admin" role assignments that allow plugin management. Please ensure that these permissions are in place.
The Synthetic Monitoring plugin may not appear in the Plugin Management section of your Azure Managed Grafana instance. This is often because not all Grafana plugins are supported in the managed environment provided by Azure.
Plugin management in Azure Managed Grafana is limited compared to self-hosted Grafana instances. Some plugins may not be available for installation due to Azure's restrictions.
https://learn.microsoft.com/en-us/azure/managed-grafana/how-to-manage-plugins
https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/grafana-plugin#sign-in-to-grafana
https://learn.microsoft.com/en-us/azure/managed-grafana/how-to-permissions?tabs=azure-portal
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