Sets a sticker set thumbnail. Request type for Tdjson#setStickerSetThumbnail.
Format of the thumbnail; pass null if thumbnail is removed.
Sticker set name. The sticker set must be owned by the current user.
Thumbnail to set; pass null to remove the sticker set thumbnail.
Sticker set owner; ignored for regular users.
Sets a sticker set thumbnail. Request type for Tdjson#setStickerSetThumbnail.