At the age of 16, Leonhard Euler defended his Master's Thesis, where he discussed and compared Descartes' and Newton's approaches to planet motion. I don't know anything else about it. In particular, I don’t know what position the young Euler supported.

Is there any modern account of this dissertation? In English or French?

Edit. The only source I know of is of dubious value, to say the least. On the occasion of a celebration of Euler's tri-centenary, I was offered a comics, authored by Andreas K. & Alice K. Heyne (illustrations by Elena S. Pini). There is a lot of good to say about it. But on page 10, block 3.1, Euler is concluding is defense with the words ... so the planets are dragged along by aether vortices. I wander whether the authors have any source to support this citation.

By the way, I wish to mention that it took a considerable time for Newton's theory of gravitation to be accepted in France, and more generally in continental Europe. Descartes' reputation was so high that any contradiction to his writings was a priori rejected. The Principia were published in 1687, but they penetrated the French scientific community only once Emilie du Chatelet translated them circa 1745, on Voltaire's request.