/usr/share/phpbb3/www/language/en_us/email/group_approved.txt is in phpbb3-l10n 3.0.10-4+deb7u3.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 | Subject: Your request has been approved
Congratulations,
Your request to join the "{GROUP_NAME}" group on "{SITENAME}" has been approved.
Click on the following link to see your group membership.
{U_GROUP}
{EMAIL_SIG}
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