i18n in Advanced Template Frontend Backend

Hello.

In advanced template, I need this config in common/config/main.php in order to get working the translations in frontend/backend:




'i18n' => [

        'translations' => [

            'app*' => [

                'class' => 'yii\i18n\PhpMessageSource',

                'basePath' => '@common/messages'

            ],

            '*' => [

                'class' => 'yii\i18n\PhpMessageSource',

                'basePath' => '@common/messages'

            ],

        ],

],



But with this configuration, only app* translations working on frontend:




'i18n' => [

        'translations' => [

            '*' => [

                'class' => 'yii\i18n\PhpMessageSource',

                'basePath' => '@common/messages'

            ],

        ],

],



So, the question is: Why in the 2nd case, if using category ‘*’ doesn’t work if I use in backend Yii::t(“app”,“Some”)?