webpackでSCSSの背景画像をBase64にしたら表示されず困ってます

Question

フロントエンドの環境構築のサンプル作ってるのですが、Base64の設定がうまく行かず困ってます。書き出しが、うまく行ってるようにみえるのですが、サイトを表示して、画像が表示されません。

検証で、pタグにbeforeのスタイルが表示れるのは確認してます。

###SCSSファイル

p:before {
  display: inline-block;
  width: 1em;
  height: 1em;
  background-image: url(../img/sample.png);
  background-size: contain;
  content: "";
}

###ビルド後のCSSファイル

p:before {
  display: inline-block;
  width: 1em;
  height: 1em;
  background-image: url(data:image/png;base64,bW9kdWxlLmV4cG9　　~~~ 長いので省略 ~~~~ DQyI=);
  background-size: contain;
  content: ""; }

###webpack.config.js

const path = require('path');
const webpack = require('webpack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const extractSass = new ExtractTextPlugin("[name].bundle.css");

module.exports = [
{

// ========================================================
// NOTE JS用モジュール
// ========================================================
  entry: {
    main: './src/js/main.js'
  },
  output: {
    path: path.resolve(__dirname, 'public/dist/js'),
    publicPath: '/js/',
    filename: '[name].bundle.js'
  },
  module: {
    rules: [
      {
        enforce: 'pre',
        test: /.js$/,
        exclude: /node_modules/,
        loader: 'eslint-loader'
      },
      {
        test: /.js$/,
        exclude: /node_modules/,
        loader: 'babel-loader'
      }
    ]
  },
  plugins: [
    /* use jQuery as Global */
    new webpack.ProvidePlugin({
      jQuery: 'jquery'
      // $: 'jquery'
    })
  ],
  resolve: {
    extensions: ['.js']
  }
},
{
// ========================================================
// NOTE CSS用モジュール
// ========================================================
  entry: {
    main: './src/scss/main.scss'
  },
  output: {
    path: path.resolve(__dirname, 'public/dist/css'),
    // publicPath: '/css/',
    filename: '[name].bundle.css'
  },
  module: {
    rules: [
      {
        test: /.(png|woff|woff2|eot|ttf|svg)(?v=[0-9].[0-9].[0-9])?$/,
        use: [
          {
            loader: 'url-loader'
          }
        ]
      },
      {
      test: /.scss$/,
      exclude: /node_modules/,
      use: extractSass.extract({
        fallback: 'style-loader',
        use:[
          'css-loader?sourceMap',
          'sass-loader?sourceMap'
          // {
          //   loader: 'postcss-loader',
          //   options: {
          //     plugins: function () {
          //       return [
          //         require('autoprefixer')
          //       ];
          //     }
          //   }
          // }
        ]
      })
    },
    {
      // 10KB以下の画像をBase64で出力
      test: /.(jpe?g|png|gif|svg|ico)(?.+)?$/,
      use: {
        loader: 'url-loader',
        options: {
          limit: 10240,
          name: '../img/[name].[ext]'
        }
      }
    }]
  },
  plugins: [
    extractSass
  ],
  resolve: {
    // style-loader の中で、.jsファイルを拡張子なしで requireしているところがあるため、'.js'が必要
    extensions: ['.css', '.js']
  }
}
];

###package.json

{
  "name": "_test",
  "version": "1.0.0",
  "description": "test",
  "main": "./src/main.js",
  "scripts": {
    "dev": "npm-run-all -p watch server",
    "release": "webpack --progress --optimize-minimize",
    "watch": "webpack --progress --colors --devtool source-map --watch",
    "server": "browser-sync start --server public --serverStatic public --files public/* || exit 0"
  },
  "keywords": [],
  "author": "sample",
  "license": "MIT",
  "devDependencies": {
    "autoprefixer": "^7.1.6",
    "babel-core": "^6.26.0",
    "babel-loader": "^7.1.2",
    "babel-plugin-espower": "^2.3.2",
    "babel-preset-env": "^1.6.1",
    "browser-sync": "^2.18.13",
    "css-loader": "^0.28.7",
    "eslint": "^4.11.0",
    "eslint-loader": "^1.9.0",
    "extract-text-webpack-plugin": "^3.0.2",
    "file-loader": "^1.1.5",
    "node-sass": "^4.6.1",
    "npm-run-all": "^4.1.2",
    "postcss-loader": "^2.0.8",
    "sass-loader": "^6.0.6",
    "style-loader": "^0.19.0",
    "url-loader": "^0.6.2",
    "webpack": "^3.8.1"
  },
  "dependencies": {
    "jquery": "^3.2.1"
  }
}