Why doesn't mix-manifest.json refresh?

My webpack.mix.js

const { mix } = require('laravel-mix');

mix.scripts([
    'node_modules/highlightjs/highlight.pack.js',
    'public/js/app.js'
], 'public/js/app.js')
.sass('resources/assets/sass/app.scss', 'public/css')
.copy('node_modules/font-awesome/fonts', 'public/fonts')
.js('resources/assets/js/app.js', 'public/js')
.version();

The version() method was obviously used but mix-manifest.json file wasn't refreshed.

mix repeatedly returns the same mix-manifest.json file.

{
  "/js/app.js": "/js/app.29dc49fed41329db45585945297fcf3e.js",
  "/css/app.css": "/css/app.42b000e5046630edd233b0eb8d2df902.css"
}

How can I refresh that?