What is the ruling on the ushers speaking in the mosque during the Friday sermon out of necessity?

The prayer of one who is preoccupied with something other than listening to the sermon is valid, as is the prayer of one who talks. However, the reward for it is incomplete, due to the Prophet's (peace and blessings be upon him) saying: "Whoever touches the pebbles has engaged in idle talk." Its meaning is that he does not have a complete Jumu'ah (Friday prayer). It is advised to teach people about the matter of advancing in the rows and making space for their brothers after the Jumu'ah prayer.