Allow modules to be disabled

lib/webpack/config.js

@@ -106,17 +106,30 @@ module.exports = async function() {
                 options: {
                   sourceMap: isDev ? 'inline' : false,
                   plugins: loader => {
-                    const defaultPlugins = () => [
-                      require('autoprefixer')({
-                        browsers: ['last 2 versions', 'IE 11']
-                      }),
-                      require('lost'),
-                      require('postcss-custom-media'),
-                      require('postcss-zindex'),
-                      require('postcss-discard-duplicates'),
-                      require('postcss-unique-selectors'),
-                      require('postcss-responsive-type')
-                    ]
+                    const defaultPlugins = (config = {}) =>
+                      [
+                        config.autoprefixer === false
+                          ? null
+                          : require('autoprefixer')({
+                              browsers: ['last 2 versions', 'IE 11']
+                            }),
+                        config.lost === false ? null : require('lost'),
+                        config['postcss-custom-media'] === false
+                          ? null
+                          : require('postcss-custom-media'),
+                        config['postcss-zindex'] === false
+                          ? null
+                          : require('postcss-zindex'),
+                        config['postcss-discard-duplicates'] === false
+                          ? null
+                          : require('postcss-discard-duplicates'),
+                        config['postcss-unique-selectors'] === false
+                          ? null
+                          : require('postcss-unique-selectors'),
+                        config['postcss-responsive-type'] === false
+                          ? null
+                          : require('postcss-responsive-type')
+                      ].filter(i => i !== null)
                     // Allow custom PostCSS configuration
                     if (themeConfig.postCss) {
                       return themeConfig.postCss(loader, defaultPlugins)