This edge release introduces the ability to configure the proxy's discovery cache timeouts via annotations. While most users will not need to do this, it can be useful to improve the mesh's resilience to control plane failures. This release also includes a number of other important improvements and bug fixes. * Added -o json flag for the `linkerd multicluster gateways` command (thanks @hiteshwani29) * Added missing label `linkerd.io/extension` to certain resources to ensure they pruned when appropriate (thanks @ClementRepo) * Fixed a memory leak in the service mirror controller * Improved validation of the `--to` and `--from` flags for the `linkerd viz stat` command (thanks @pranoyk) * Fixed an issue with W3C trace context propagation which caused proxy spans to be siblings rather than children of their original parent (thanks @whiskeysierra) * Updated the Linkerd CNI plugin base docker image from Debian to Alpine * Fixed an issue where specifying a `remote_write` config would cause the Prometheus config to be invalid (thanks @hiteshwani29) * Added the ability to configure the proxy's discovery cache timeouts with the `config.linkerd.io/proxy-outbound-discovery-cache-unused-timeout` and `config.linkerd.io/proxy-inbound-discovery-cache-unused-timeout` annotations * Fixed the `linkerd viz check` command so that it will wait until the viz extension becomes ready * Fixed an issue where meshed pods could not communicate with themselves through a ClusterIP Service