What is the ruling on Qunut in Fajr prayer, and is what Sheikh Ahmad Shakir said in Sunan al-Tirmidhi correct, that the hadiths about Qunut are authentic and what is forbidden is Qunut on a permanent basis?

The practice of Qunut in Fajr prayer is a matter of differing opinions among jurists. Some consider it a Sunnah (recommended) or Mustahabb (desirable), such as the Shafi'is and Malikis. Others, like the Hanafis and Hanbalis, deem it not legislated. While some authentic hadiths regarding Qunut have been reported, they are not specific to Fajr prayer, and the disagreement concerning its consistent practice is ancient. Al-Tirmidhi narrated from Al-Bara' bin Azib that the Prophet (peace and blessings be upon him) used to perform Qunut in the Fajr and Maghrib prayers. Scholars have differed on this matter; some Companions and Tabi'un, as well as Malik and Shafi'i, hold the view of Qunut in Fajr, while Ahmad and Ishaq believe that Qunut should only be performed in times of calamity (Nawazil). Scholars are in agreement on abandoning Qunut without cause in the other four prayers (Dhuhr, Asr, Maghrib, and Isha).