trict the set of namespaces that are part of the mesh. A <a href=/v1.19/docs/reference/config/networking/sidecar/>Sidecar</a> resource also controls the visibility of sidecar configurations and what gets pushed to the sidecar proxy. What are the differences between them?</p><ul><li>The <code>discoverySelectors</code> configuration declares what Istio control plane watches and processes. Without <code>discoverySelectors</code> configuration, the Istio control plane watches and processes all namespaces/servic