Vuejs 3: Problem with vue-template-compiler

To make vue 3 work fine with webpack without using vite or vue cli follow these steps :

1. init the package.json like :

{
    "private": true,
    "name": "vue-3",
    "description": null,
   
}

2. install the last version of vue :

npm i --save vue@next vue-loader@next

3. install also the dev dependencies that includes @vue/compiler-sfc which replaces vue-template-compiler

npm i -D @vue/compiler-sfc css-loader file-loader mini-css-extract-plugin
 url-loader webpack webpack-cli webpack-dev-server

• @vue/compiler-sfc
• css-loader
• file-loader
• mini-css-extract-plugin
• url-loader
• vue-loader
• webpack
• webpack-cli
• webpack-dev-server

4. create or edit your webpack.config.js with following content :

const path = require("path");
const { VueLoaderPlugin } = require("vue-loader");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");

module.exports = (env = {}) => ({
  mode: env.prod ? "production" : "development",
  devtool: env.prod ? "source-map" : "cheap-module-eval-source-map",
  entry: [
    require.resolve(`webpack-dev-server/client`),
    path.resolve(__dirname, "./src/main.js")
  ].filter(Boolean),
  output: {
    path: path.resolve(__dirname, "./dist"),
    publicPath: "/dist/"
  },
  resolve: {
    alias: {
      // this isn't technically needed, since the default `vue` entry for bundlers
      // is a simple `export * from '@vue/runtime-dom`. However having this
      // extra re-export somehow causes webpack to always invalidate the module
      // on the first HMR update and causes the page to reload.
      vue: "@vue/runtime-dom"
    }
  },
  module: {
    rules: [
      {
        test: /\.vue$/,
        use: "vue-loader"
      },
      {
        test: /\.png$/,
        use: {
          loader: "url-loader",
          options: { limit: 8192 }
        }
      },
      {
        test: /\.css$/,
        use: [
          {
            loader: MiniCssExtractPlugin.loader,
            options: { hmr: !env.prod }
          },
          "css-loader"
        ]
      }
    ]
  },
  plugins: [
    new VueLoaderPlugin(),
    new MiniCssExtractPlugin({
      filename: "[name].css"
    })
  ],
  devServer: {
    inline: true,
    hot: true,
    stats: "minimal",
    contentBase: __dirname,
    overlay: true,
    injectClient: false,
    disableHostCheck: true
  }
});

5. Add dev script to run your app :

{
    "private": true,
    "scripts": {
        "dev": "webpack-dev-server"
    },
    "dependencies": {
        "vue": "^3.0.2"
    },
    "name": "vue-3",
    "description": null,
    "devDependencies": {
      ...
    }
}

6. Fill the index.html with following content :

<link rel="stylesheet" href="/dist/main.css" />
<div id="app"></div>
<script src="/dist/main.js"></script>

Finally run npm run dev the visit http://localhost:8080/

for a ready to use project try to clone this REPOSITORY which built by following the steps above.

I believe you need to use vue-loader@next with Vue 3

In Vue 3 the SFC compiler package is no longer vue-template-compiler but compiler-sfc (check here)

I completely agree with the suggestion to use Vue CLI to manage the project - it will save you lot of trouble managing all the dependencies (especially now when Vue 3 ecosystem is trying to catch-up with Vue 3 release and lots of tool event don't have any migration documentation ....like vue-loader)

If you are not able to use CLI because your existing project already have Webpack config, you can still use CLI as a guide. Just generate new project on the side, use vue inspect command to inspect Webpack config it is using and package.json for required dependencies...