htmlWebpackPlugin.options.title

JavaScript
//vue.config.js
module.exports = {
  chainWebpack: config => {
    config
      .plugin('html')
      .tap(args => {
        args[0].title = "Popular films";
        return args;
      })
  }
}// Put this into /vue.config.js
module.exports = {
  chainWebpack: config => {
    config
      .plugin('html')
      .tap(args => {
      args[0].title = '<Your new title>';	// Replace your title here
      return args;
    });
  }
};
Source

Also in JavaScript: