How a worshipper prays on a chair in congregation

Question:
The questioner says: If the one who prays on a chair prays with the congregation, what does he align with those around him, his shoulder or his foot?

Answer:
My brother, praying on a chair is an exceptional case; the worshipper does what he is able to do. But here are some observations: they should pray on chairs behind the imam. It is preferable that they be far from the imam, and that the front row behind the imam be occupied by the qurra' (reciters) and the people the imam needs. The Prophet (peace and blessings be upon him) said: The imam may need them to alert him or to appoint a substitute from among them when necessary. They should leave the space directly behind the imam for the healthy people. They should be on the sides. That is one point.
The second point is that they bring large chairs that take up space in the row and crowd the worshippers and the rows behind. So they should bring a small chair, just enough for the need. There are small chairs available that are just the right size. He should choose a small chair that is just enough for the need. He prays on it, and praise be to Allah. Yes.