Is discharge during intercourse a requirement for a fast to be invalidated?
No; any act of intercourse, even without discharge, invalidates the fast.
Which matters that invalidate the fast are specifically mentioned in the Qur’an?
Three major matters that invalidate the fast are mentioned in the Qur’an. They are intercourse, eating, and drinking. “So now have sexual relations with them and seek that which Allaah […]