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I installed 2 languages in my joomla (Japanese and Korean).
I created some categories in Korean.
I'd like to provide Japanese category name to Japanese user.
How can I create translated category name?
If you are meaning the group categories these are changed directly in Jomsocial admin administrator/index.php?option=com_community&view=groupcategories you can edit the group category name and enter any text you wish
I created the group in Korean under site language is Korean.
You mean that change the language of site to Japanese then change category's name to Japanese?
If you so then it should be showing the Korean category name when I change language to Korean but it doesn't work.
"Create category in Korean" > "Change language of site to Japanese" > "Change category name to Japanese" > Check under site language is Korean but it shows Japanese name"
as you can see the string paramater is not using latin text, you should use latin dont use korean, and on the line 3005 you are missing the double quote.
beside that all other japanase translations are still using english version, please you check it.