Is it permissible to commit an innovation (bid‘ah)—such as reciting the Qur’an at banquets or making congregational supplications after prayer—in order to avoid people's discord and the fragmentation of the mosque community?

It is not permissible for a Muslim to commit a forbidden innovation (bid'ah) under the pretext of uniting people, though it is permissible to forgo a recommended act (mustahabb) to reconcile hearts. It is obligatory to advise people and warn them against innovation, not to participate in it with them. An innovation committed by someone looked up to will solidify it. Hearts are united by obedience to Allah and His Messenger, not by innovations.