Study of food preference in Archosauria reptiles

There are many groups in the vertebrate life of the Mesozoic in Earth history that no longer exist today (e.g., dinosaurs, pterosaurs) or are represented today by very few species (e.g., crocodiles). A very important and really little researched questions is what and how these once animals were fed.
The aim of the research is to obtain a more accurate picture of the food processing of each species and the quality of the food consumed through a three-dimensional scanning and comparison of the teeth and the analysis of the wear surfaces on the teeth.

How, at what pace and in which groups did the spread of plant-eating start on our Earth after the mass extinction event on the Permian-Triassic mass extinction?

Is there a correlation between the appearance of herbivorous vertebrates, which is becoming more frequent at the end of the Jurassic period and the beginning of the Cretaceous period, and the spread of flowering plants?