DEBUG: configure:10169: checking for nss-config
DEBUG: configure:10204: checking for NSS - version >= 3.32.1
DEBUG: configure: error: you don't have NSS installed or your version is too old
ERROR: old-configure failed
*** Fix above errors and then restart with\
               "make -f client.mk build"
make: *** [client.mk:383: configure] Error 1
 * ERROR: www-client/firefox-56.0::gentoo failed (configure phase):
 *   emake failed
 * 
 * If you need support, post the output of `emerge --info '=www-client/firefox-56.0::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=www-client/firefox-56.0::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/www-client/firefox-56.0/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/www-client/firefox-56.0/temp/environment'.
 * Working directory: '/var/tmp/portage/www-client/firefox-56.0/work/firefox-56.0'
 * S: '/var/tmp/portage/www-client/firefox-56.0/work/firefox-56.0'

>>> Failed to emerge www-client/firefox-56.0, Log file:

>>>  '/var/tmp/portage/www-client/firefox-56.0/temp/build.log'