Why did Textus Receptus add the word “Χριστοῦ” to [Revelation 12:17]?

Rome’s persecution of specific Israelites who have "τὴν μαρτυρίαν τοῦ Ἰησοῦ" was poetically documented in [Revelation 12:17] – "And the dragon was enraged with the woman, and he went to make war with the rest of her offsprin…