What is the ruling on repeating in unison: "O Allah, You are Forgiving and love forgiveness, so forgive us," in the mosque on Laylat al-Qadr?

Reciting the supplication, "O Allah, You are Pardoning and love to pardon, so pardon me," is legislated, especially on the Night of Decree (Laylat al-Qadr). Gathering to recite it is good and desirable, as long as it does not become a regular habit or is associated with a reprehensible innovation.