How to stop mamp pro overriding localhost:3000?

Question

I am trying to get an existing node website working for me locally with mamp pro. The first developer used the non-pro version of mamp and it works fine for him. But when I visit http://localhost:3000/ after "npm start" I am served with the mamp pro default "The virtual host was set up successfully" page. Is there a way I can prevent mamp pro superseding localhost or even just that port? (I tried the solutions suggested here and here but it just redirected it to the mamp default page again.) Webpack.config settings here:

proxy: [
  {
    context: [
      '**',
      '!/*.js',
      '!/*.css',
      '!/__webpack_hmr',
      '!/*.hot-update.js',
      '!/*.hot-update.json',
    ],
    options: {
      target: 'http://example.local:8888/',
      autoRewrite: true,
      // Review docs before setting these
      // changeOrigin: true,
      // logLevel: 'error'
    },
  },
],

},