js-refactor doesn't work on new files

[jmanuel1]

I'm not sure if the issue is in js-refactor or refactor, but...

If I create a new file using application:new-file so that I get an untitled file, write a bit of JS like

let aVar = 6
console.log(`aVar is ${aVar}`)

and then save the file as something.js, refactoring doesn't work. The underlines don't appear and the refactor:rename command seems to do nothing.

Expected behavior: Refactoring works once the editor grammar is changed to JavaScript.