You can use your browser's developer tools:
Ruby (Rails application)
Below are two options for "live"-debugging Ruby code (i.e., while the application is running).
pry and set
binding.pry breakpoints in your Ruby code:
https://docs.gitlab.com/ee/development/pry_debugging.html. Pry should work independently of your IDE.
Visual Studio Code
If you're using the Visual Studio Code IDE, you can use it's visual / GUI debugger. The configuration depends on your local setup, however, following these instructions should get you started fine:
In case debugging doesn't work yet, have a look at the following resources to fine-tune your configuration: