Narrated Hafs bin `Asim
Ibn `Umar went on a journey and said, "I accompanied the Prophet (ﷺ) and he did not offer optional prayers during the journey, and Allah says: 'Verily! In Allah's Messenger (ﷺ) you have a good example to follow.' " (33.21)
Narrated Ibn `Umar
I accompanied Allah's Messenger (ﷺ) and he never offered more than two rak`at during the journey. Abu Bakr, `Umar and `Uthman used to do the same.