It is not Sunnah to say du‘aa’ following an obligatory prayer, placing the right hand on the forehead

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Check below answers in case you are looking for other related questions:
What is meant by dhikr and du‘aa’ at the end of the prayer?
Reciting the opening takbeer quietly in a prayer in which Qur’aan is to be recited out loud

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Related Answers:
He sneezed whilst he was praying – should he say al-hamdu Lillaah?
Sending blessings upon the Prophet (blessings and peace of Allaah be upon him) when he is mentioned in obligatory and naafil prayers
Ruling on prayer if one omits some obligatory parts out of ignorance or forgetfulness
What is meant by dhikr and du‘aa’ at the end of the prayer?
Reciting the opening takbeer quietly in a prayer in which Qur’aan is to be recited out loud

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