media_attachments: {
        supported_mime_types: MediaAttachment::IMAGE_MIME_TYPES + MediaAttachment::VIDEO_MIME_TYPES + MediaAttachment::AUDIO_MIME_TYPES,
        image_size_limit: MediaAttachment::IMAGE_LIMIT,
        image_matrix_limit: Attachmentable::MAX_MATRIX_LIMIT,
        video_size_limit: MediaAttachment::VIDEO_LIMIT,