Why are extra .js and .css files being auto-generated in my Shopify theme editor?

I have been working with the prestige theme and the editor is alright for shopify, then I noticed on another shopify account where the dawn theme is installed there is a completely new interface for editing themes.

So today I noticed on the account I have been working on the editor has changed for the prestige theme and what I don’t understand is I had a product.js.liquid file originally and now I have a product.js.liquid file and shopify is generating a product.js file. They are doing the same thing with the css files. I had a custom.css.liquid file and now there are two files. One is custom.css.liquid and the other one is custom.css.

Should we be deleting the js.liquid and .css.liquid files? I don’t know why there are files being auto generated now and why I can’t find any docs on this. Then if I try to change anything in the product.js file I get an error saying I cannot override a generated file. Any info on this would be appreciated

Ok, my question is why shopify started doing this and if there are any docs on this, yesterday this was not happening and today the whole code editor is different