The Messenger of Allah ﷺ forbade sitting with one's knees drawn up and wrapped in a garment during the Friday sermon while the imam is delivering the khutbah.
أن رسول الله ﷺ نهى عن الحبوة يوم الجمعة والإمام يخطب.
Abu Dawud (1110) and Tirmidhi (514) both narrated it through Abdullah bin Yazid Muqri, who said, Saeed bin Abu Ayub narrated to us, from Abu Marhum, from Sahl bin Muaz bin Anas, from his father, and he related the hadith. Its isnad is hasan, because of Abu Marhum (whose name is Abdul-Rahim bin Maymun Madani), for there is disagreement about him, though his hadith is hasan. Sahl bin Muaz presents no problem. Tirmidhi said, "This is a hasan hadith." Ibn Khuzayma (1815) and Hakim (1/289) graded it sahih, both narrating it through this same route. Hakim said, "This is a hadith sahih in isnad, though the two of them did not include it."As for the phrase "he forbade hibwah," it is said as hibwah with the ha vowelled with kasrah, and hubwah with dammah, the kasrah form being more common. Ihtiba is when a person wraps a garment around his back and legs. Khattabi stated this in Gharib al-Hadith (3/37-38).As for what Abu Dawud (1111) narrated from Yaala bin Shaddad bin Aws, who said, "I was present with Muawiya at Bayt al-Maqdis. He gathered us together, and I looked and saw that most of those in the masjid were companions of the Prophet ﷺ, and I saw them sitting in ihtiba while the imam was delivering the sermon," this is daif. It was narrated solely by Khalid bin Hayan Raqqi, from Sulayman bin Abdullah bin Zubarqan, from Yaala bin Shaddad. Ibn Zubarqan was deemed reliable only by Ibn Hibban, and no one narrated from him except Raqqi, and Raqqi is disputed. Hafiz said of him, "Truthful but makes mistakes," and said of Ibn Zubarqan, "Weak in hadith."Likewise, what has been narrated from Ibn Umar, that he used to sit in ihtiba while the imam was delivering the sermon, is not sound. Bayhaqi narrated it (3/235), and in its isnad is Ayub bin Suwayd, who is daif, having been declared daif by Ahmad and others. Something similar has been narrated from other companions as well, but none of it is established as reliable.