Which is better for the traveler: shortening the prayer in his place of residence or performing it in full with the congregation in the mosque?

If you find people praying in congregation, shortening their prayers (qasr) in your place of residence, then it is better to pray with them to combine the virtue of congregational prayer with the Sunnah of shortening prayers. However, if praying individually with qasr conflicts with praying in congregation with complete prayers (itmam), then it is better to pray with the mosque's congregation due to the agreed-upon virtue of congregational prayer, whereas shortening prayers is a matter of differing opinions. As for praying individually due to the absence of a congregation, then shortening prayers is better, as it is the Sunnah of the Prophet (peace be upon him) and his successors, and it is a concession from Allah that He loves to be accepted.