fluentd-ui/config/webpack/loaders/vue.js

const { dev_server: devServer } = require('@rails/webpacker').config

const isProduction = process.env.NODE_ENV === 'production'
const inDevServer = process.argv.find(v => v.includes('webpack-dev-server'))
const extractCSS = !(inDevServer && (devServer && devServer.hmr)) || isProduction

module.exports = {
  test: /\.vue(\.erb)?$/,
  use: [{
    loader: 'vue-loader',
    options: { extractCSS }
  }]
}