As a sidenote, I think the new JS curriculum will help you “see” the JavaScript changes because the new curriculum is focused on learning by building projects.
When you make changes to your javascript code, you will be building a project at the same time and test out the functionality while you are building the project.
In the beginning, it can be hard to put the pieces to together and fully understand how javascript is supposed to work on a web page.
But once you start building projects and see your changes affect the interactivity on the web page, then it will start to make more sense.