Is it necessary to set system locale and timezone before I update world according to set flags in /etc/portage/make.conf (in Arch Linux case before I configure host name, regular user etc.)?
Will something bad happen with file metadata (creation time, modify time etc.) or other system data if I set incorrect timezone or don't set timezone at all? What wrong could happen if I forget to set locale before updating world while being inside chroot? Does generated locale together with locale set in /etc/locale.conf affect runtime files and working software on the installed system or it affect only how software presents data for the user? Is it okay to have set L10N="en-US pl de" and only enabled en_US.UTF-8 UTF-8 pl_PL.UTF-8 UTF-8 in /etc/locale.gen? Is it necessary on systemd installations to run systemd-firstboot after installing system? Can I type only command systemctl preset-all and skip systemctl preset-all --preset-mode=enable-only if I'm doing Gentoo systemd installation? What is the difference between systemctl preset-all --preset-mode=enable-only and systemctl preset-all?
