workaround: RUN mkdir /usr/aarch64-unknown-linux-gnu/usr/include/X11/ -p RUN n -s /usr/aarch64-unknown-linux-gnu/usr/include/X11/ /usr/include/X11
Oh, I accidently pressed summit, sorry Using crossdev in docker on a clean up-to-date system with default settings beside some ugliness to bypass https://bugs.gentoo.org/558774 https://bugs.gentoo.org/641886 and https://bugs.gentoo.org/641882
This is not a Prefix bug, please take it up with crossdev.