Starting with Kubernetes 1.20, released on December 8th, developers have received a warning that Kubernetes is deprecating Docker. This means that Kubernetes officially ceases to support the Docker tech stack, as you can already see in the release notes on GitHub.
The news wasn’t a big surprise. The Kubernetes development team had been planning and preparing this step for three years, so it was only a matter of time. Since Kubernetes was originally developed to orchestrate Docker containers, many Kubernetes users probably didn’t like this.