Version 20231115 is available upstream. Please consider updating! It seems that version 20231115 is available upstream, while the latest version in the Gentoo tree is 20180315. You think this warning is false? Read more about it here.
Japanese translation of portage/gentoolkit man pages are contributed by
Gentoo Linux User Group Japan and maintained by that mailing list
(gentoojp-docs@ml.gentoo.gr.jp). All questions and comments should be
posted to that list with regard to man pages translation for
portage/gentoolkit.