There is a mistake of translation in russian http://screencast.com/t/G2GhpI58B
The phrase "Удаление завершено" in completed tasks is incorrect, because it means "Deleting is completed". The correct one should be "Удалить завершённые (задачи)".
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Please note that the original text is: "Delete completed" and not "Delete completed (tasks)" so shouldn't "Удалить завершённые" be the correct translation?