I am asking about the etiquette of disagreement in jurisprudential matters.

The اختلاف (difference of opinion) among scholars in matters of Fiqh (Islamic jurisprudence) is a mercy and an expansion for those accountable (Mukallafun). Allah did not establish conclusive evidence for all শরীয়াহ (Islamic legal) rulings; rather, He made them probabilistic (Zanniyyah). Among the etiquettes of scholarly debate (Munazara) are: avoiding stubbornness, arrogance, showing off (Riya'), and boasting; paying attention to what the opponent says and not belittling their opinion; and exercising patience and self-control. As Imam Al-Shafi'i said:

If you possess virtue and knowledge, Then debate with whom you debate, in tranquility. He will benefit you from what he has gained, without expecting gratitude, And beware of obstinacy and those who show off. Indeed, evil within these aspects Leads to estrangement and animosity.