pfSense

guiconfig.inc
function print_info_box_np($msg, $name="apply",$value="Apply changes")

This function is called with gettext (firewall_rules.php)
print_info_box_np(gettext("The firewall rule configuration has been changed.<br>You must apply the changes in order for them to take effect."));

But in function body check $msg param
...
if(stristr($msg, "apply") != false || stristr($msg, "save") != false || stristr($msg, "create") != false) {
...

If GetText translate $msg, then this is code nothing to find in $msg variable.

Result: if i enable translation settings for pfSense (with translated string), then "Apply changes" button never be shown. Only 'Close' button.

Maybe need inspect code for this GetText logical bugs?