Hey
All new Mendix 10 client api you can find on this link https://apidocs.rnd.mendix.com/10/client/mx.session.html
I believe in Mendix 10 cleint Api will not provide you solution where you can just time one function, you wanna use this one context.getTrackEntity(); // "MyFirstProject.Pizza" but you will need to combine couple of action together to make it work. Please let me know if i can help you more or if you find better solution
Best regards, Slavko