Shaykh Abu Abdir Rahmaan Yahyaa bin Alee Al-Hajooree was asked:
Clarify for us how to detest the congregational supplication after the prayer. Is it by leaving the masjid or [is it by] sitting in the back [of the masjid] and detesting it with the heart only?
فَاتَّقُوا اللَّهَ مَا اسْتَطَعْتُم
So keep your duty to Allah and fear Him as much as you can
And in the Hadith of Abu Sa’eed al-Khudri (may Allah be pleased with him):
من رأى منكم منكرًا فليغيره بيده, فإن لم يستطع فبلسانه, فإن لم يستطع فبقلبه وذلك أضعف الإيمان
He who amongst you sees something abominable should modify it with the help of his hand; and if he has not strength enough to do it, then he should do it with his tongue, and if he has not strength enough to do it, (even) then he should (abhor it) from his heart, and that is the least of faith
[Muslim no. 49]
So if you are able to change it with your tongue, then clarify to the people the opposition of this action and that these remembrances which are performed in congregation and these supplications which are performed in congregation after the prayer are newly-invented matters.
Ibn Masud (may Allah be pleased with him) said when he entered upon the companions of the masjid of Abi Hanifa:
: أيها الناس, فقتم أصحاب رسول الله صلى الله عليه وآله وسلم علمًا، أم جئتم بدعة ظلمًا؟ والله هذه آنية سول الله صلى الله عليه وآله وسلم لم تكسر وثيابه لم تبلَ وقد أحدثتم في دين الله ما أحدثتم
Oh People, [is it the case that] you have either surpassed the Companions of the Messenger of Allah in Knowledge or you have come with an oppressive innovation? By Allah, these are the vessels of the Messenger of Allah which have not been broken and his clothing is still wet and you have innovated in the religion of Allah what you have innovated.
[Sunan Daraami (no. 210)]
Detest [that] with what you can. If you cannot, then it is for you to busy yourselves with the remembrance of Allah, the Exalted, between you and Allah, in terms of Tasbeeh, Tahmeed, Takbeer, Tahleel and from the remembrances of the prayer. You should leave and in your leaving [the masjid] there is a rebuke [against] them if you are from the people of importance in that place or at the very least you will be safe from their clamour, which will busy you from remembrance of Allah, the Exalted”
[al-Iftaa ‘ala asila til-waaridah min dawl shatta pg. 199]
This is also the opinion of Shaikh Ahmad an-Najmi rahimahullah where he said that this innovation can be detested by the tongue or the hand depending on the person’s ability. You can see more on his opinion here.
Faisal Ibn Abdul Qaadir Ibn Hassan