fix crouton Xorg.crouton.*.log error without reboot just $ sudo rm /tmp/Xorg.crouton.* Tada ! It's work again ❤️
delete chroot when you made some terrible mistakes in chroot show all installed chroot $ sudo edit-chroot -a delete chroot which one you want never see it $ sudo edit-chroot -d chrootname >default chroot name should be xenial