Manjor update:
今天manjaro更新，黑屏光标闪烁，ctrl + alt +f6 进入命令界面.
error while loading shared libraries: libidn2.so.4: cannot open shared object file: No such file or directory
google解决方法

1.chroot
2.pacman -U /var/cache/pacman/pkg/libidn2-2.0.5-1-x86_64.pkg.tar.xz
3.cp /var/cache/pacman/pkg/libidn2-2.1.0-1-x86_64.pkg.tar.xz ~
  cd ~
  tar xf libidn2-2.1.0-1-x86_64.pkg.tar.xz
4.cp usr/lib/libidn2.so.4* /usr/lib/
5.pacman -S libidn2 --force
6.pacman -Syu
7.pacman -S systemd
  exit
  reboot

After successful boot run
sudo pacman -Syyuu