Are the two prostrations of forgetfulness (sujood al-sahw) performed before or after the tasleem if the Imam mistakenly stood for a fifth rak'ah, then immediately sat down before fully straightening up due to the worshippers' alert?

If a worshiper makes a mistake and stands up for an extra rak'ah, he must sit down immediately without saying the takbir. The ruling on the prostration of forgetfulness (sujud al-sahw) in this case has two scenarios:

1. If he remembers after he has risen and his thighs or knees have lifted off the ground: He prostrates for forgetfulness after the salam, because he added to his prayer.

2. If he remembers before he rises or before his thighs or knees leave the ground: He does not have to prostrate, because he is still considered to be sitting.