Visual Studio Code makes the problem (line break in the middle of the "final" value) pretty obvious...

You don't need to install any VSC extensions. I would just start using it as-is for now and only start looking into extensions once you've got more comfortable with how it works.

Also, if you do that, it'll have some time to learn about the sorts of things you are doing and will then recommend extensions for you based on what it has learned ;-)