The current qqq documentation for the notification-header-login-success message says:

Text of notification for when someone successfully logs in as the current account from a computer that has not been previously used by that account. This is shown in the user's echo notifications, and is possibly emailed to the user.

    $1 = Username for account, formatted for display
    $2 = Username for account, unformatted for use in GENDER

The actual message in English doesn't have $1, $2, and GENDER. I can understand where can $2 be useful for GENDER: in Hebrew, for example, it's good for the word "you", and in other languages it can be useful on other words. But where is $1, "formatted for display", used?

The message in English should probably use $2 and GENDER, for example as {{GENDER:$2|you}}. This will make it easy for translators, with translatewiki.net insertables, etc. Also, if $2 doesn't appear in English, then translatewiki.net shows warnings, which are unnecessary. Or, if $2 is not actually implemented, they are correct, and the qqq is misleading.

$1 should either be explained better or removed from the qqq.

Thanks!