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upgrade.md

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+# Upgrade Steps
+
+Because webpack 5 is a massive release with its own set of breaking changes,
+it's especially important that you take the time to test your build after upgrading to Mix 6.
+
+```bash
+npm install laravel-mix@next
+```
+
+# Breaking Changes
+
+Below, you'll find a short list of the most notable Mix changes that you should be aware of. Don't worry: this will only take you a moment to update.
+
+### API for JavaScript Frameworks
+
+Laravel Mix was originally built to be quite opinionated. One of these opinions was that Vue support should be provided out
+of the box. Any call to `mix.js()` would instantly come with the benefit of Vue single-file components.
+
+Though we're not removing Vue support by any stretch, we _have_ extracted Vue to its own "featured flag": `mix.vue()`.
+
+##### Before
+
+```js
+mix.js('resources/js/app.js', 'public/js');
+```
+
+##### After
+
+```js
+mix.js('resources/js/app.js', 'public/js').vue();
+```
+
+Think of this as your way of saying, "I want to compile my JavaScript **and also** add Vue support."
+
+The same is true for React.
+
+##### Before
+
+```js
+mix.react('resources/js/app.js', 'public/js');
+```
+
+##### After
+
+```js
+mix.js('resources/js/app.js', 'public/js').react();
+```
+
+### Vue Configuration Changes
+
+In line with the previous change, any Vue-specific configuration that was stored on the global `Config` object should now
+be passed directly to the `mix.vue()` call, like so:
+
+##### Before
+
+```js
+mix.js('resources/js/app.js', 'public/js').options({
+    extractVueStyles: true,
+    globalVueStyles: false
+});
+```
+
+##### After
+
+```js
+mix.js('resources/js/app.js', 'public/js').vue({
+    extractStyles: true,
+    globalStyles: false
+});
+```
+
+### Goodbye Node Sass
+
+Previous versions of Mix supported both the Dart and Node bindings for Sass. If we detected that `node-sass` was installed for your project, we'd use it. However, due to the number of issues that surround the `node-sass` implementation, as part of Mix 6, we
+will exclusively install and use the Dart-specific version (`sass`).
+
+> Notice the slight property name change: `extractVueStyles` => `extractStyles`.
+
+##### Before
+
+```js
+mix.sass('resources/sass/app.sass', 'public/css', {
+    implementation: require('node-sass')
+});
+```
+
+##### After
+
+```js
+mix.sass('resources/sass/app.sass', 'public/css');
+```
+
+# New Features
+
+-   Support for webpack 5
+-   Support for Vue 2 and 3 applications
+-   **Component:** `mix.alias()`