Is it permissible for a traveler, upon passing through a town where Friday prayer is observed, to pray Jumu'ah behind the Imam, or should he pray Dhuhr two rak'ahs shortened?

A traveler is not obliged to stop in a town to attend Friday prayer, nor is a group of travelers allowed to establish it during their journey. However, if a traveler stops in a town and attends the Friday prayer with the residents, it becomes obligatory for him to pray it with the Imam as Jumu'ah. It is not permissible for him to intend it as a shortened Dhuhr prayer, and if he does so, his prayer is invalid. Imam Al-Nawawi said: "If one prays Dhuhr behind someone who is praying Jumu'ah, the established opinion is that shortening (Qasr) is not permissible at all." Al-Buhuti mentioned that "a traveler's intention of Dhuhr behind a Jumu'ah Imam is invalid, textually; due to the disagreement with the Imam." Ibn 'Uthaymeen stated that if a traveler attends Jumu'ah and intends it as Dhuhr, his prayer is invalid.