Version 0.14.0 is available upstream. Please consider updating! It seems that version 0.14.0 is available upstream, while the latest version in the Gentoo tree is 0.11.2. You think this warning is false? Read more about it here.
buildx is a Docker CLI plugin for extended build capabilities with BuildKit.
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner.