The Messenger of Allah ﷺ forbade sleeping before it and conversation after it.
حدثنا وكيع حدثني إبراهيم بن طهمان قال سمعت أبا المنهال
نهى رسول الله ﷺ عن النوم قبلها والحديث بعدها
Its isnad is sahih. It was mentioned previously with this wording and this chain of transmission. See 19677 and its cross-references.