pfSense

As the notes in services_ntpd_gps.php suggest, you can modify it to support multi-language display:

Before modification:
$section->addInput(new Form_StaticText(
'Notes',
'A GPS connected via a serial port may be used as a reference clock for NTP. If the GPS also supports PPS and is properly configured, ' .
'and connected, that GPS may also be used as a Pulse Per Second clock reference. NOTE: A USB GPS may work, but is not recommended due to USB bus timing issues.' . '<br />' .
'For the best results, NTP should have at least three sources of time. So it is best to configure at least 2 servers under ' .
'<a href="services_ntpd.php">Services > NTP > Settings</a>' .
' to minimize clock drift if the GPS data is not valid over time. Otherwise ntpd may only use values from the unsynchronized local clock when providing time to clients.'
));

After modification:

$section->addInput(new Form_StaticText(
_('Notes'),
sprintf(
_(
'A GPS connected via a serial port may be used as a reference clock for NTP. If the GPS also supports PPS and is properly configured, ' .
'and connected, that GPS may also be used as a Pulse Per Second clock reference. NOTE: A USB GPS may work, but is not recommended due to USB bus timing issues.' . '<br />' .
'For the best results, NTP should have at least three sources of time. So it is best to configure at least 2 servers under ' .
'<a href="services_ntpd.php">Services > NTP > Settings</a>' .
' to minimize clock drift if the GPS data is not valid over time. Otherwise ntpd may only use values from the unsynchronized local clock when providing time to clients.'
)
)
));

Similar ones include services_ntpd_pps.php, firewall_pflow.php, system_gateway_groups_edit.php