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I managed to translate all phrases but can't find any reference to the line that is underneath the editor. "You can use BBCode in your post."
Can anyone point me to the $Definition I'm searching for?
Looks like they haven't included the locale, it is hard coded in plugins/ButtonBar/buttonbar.js file.
You could edit that directly and add an issue here:
Note they are fairly busy, so be patient.
grep is your friend.