Is it permissible for worshipers to say "Lā ilāha illā Allāh" (There is no god but Allah) if the Imam says "ʿIbād Allāh" (O servants of Allah) during the Friday sermon?

What is prescribed for the worshipper during the Imam's sermon is listening and paying attention. Any speech that distracts from this is considered idle talk, even if it is enjoining good, and nothing is exempted unless absolutely necessary. Scholars have unanimously agreed that listening and paying attention is better than being occupied with dhikr (remembrance of God), reciting the Qur'an, or making supplications. Therefore, saying "La ilaha illa Allah" (There is no god but Allah) when the Imam says "Servants of Allah" is not prescribed, and it has not been established in the Sunnah or the practice of the Companions. There is a concern that it might be an innovation.