Just discovered this into index.english.php
$txt['mention'] = 'Notifications';
$txt['notifications'] = 'Notifications';
I think should be:
$txt['mention'] = 'Notifications';
$txt['notifications'] = 'Notifications and email';
The first one is used in the top menu, while the second in Modify Profile > Notifications and email
In italian version on transifex they were both translated as "notifications and email". (corrected)
I will update this topic if I'll find other duplicates or translations that should be reviewed.