_spikeExtension does not work with pug-static-loader

Having index.pug in views and this in app.js:

    module: {
      rules: [{
        test: /\.pug$/,
        use: [{
          loader: 'pug-static-loader',
          options: {
            _spikeExtension: 'html',
            pretty: false,
            locals: { foo: 'bar' }
          }
        }]
      }]
    }

leads to getting index.pug in the public folder.