Today the Congregation for the Doctrine of the Faith (which absorbed my old office, the Pontifical Commission “Ecclesia Dei“) issued a decree making it possible to celebrate saints canonized after 1906 using the traditional Missale Romanum. HERE
In another decree they also approved new prefaces. HERE and explanation HERE
These new (for the TLM) Prefaces are taken from the Novus Ordo Missal, which in turn were mostly from ancient sources. The standard traditional conclusions are imposed on them. Also, there are three old texts from French and Belgian sources were were in use before Vatican II. They can – not must – be used when celebrating Mass with the traditional Missale Romanum, much like even now we can use the so-called Gallican Prefaces (e.g., for Advent).