How to debug SSR application

[camohub]

I am sorry but I really dont know how to post this question to get an answer. I need to debug SSR application but I can not use console.log(). I found this page https://nuxtjs.org/blog/nuxtjs-from-terminal-to-browser which describes something similar but without the explanation. I see the code on the pictures works but dont understnad how is it possible. I dont see any logs nor in terminal nor in the browser console. What should I set up? I dont understand the behavior cause the JS code is generated on the server BUT it is executed in the browser. Why console.log() does not work in the methods or mounted hooks?

Thanks for help.