As group admin, you can moderate the translation, like users could translate and store everything only as suggestions and when reviewed by the group admin, they can be approved or denied. Also, moderated, the imported strings can be stored as suggestions only. It is up to you to keep the language open for translations directly or moderate and check yourself every phrase. The whole content needs checking anyway. I've set you as group admin of the Turkish language, you may need to re-login.

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RAk