Feature Request: Add 'open' as an option.

The previous BrowserSync dev server had an open: true option that would open the browser window when the server started.

Would be nice to have that added back in. This horrible hack (nearly) works:

// server.js
const DEFAULT_OPTIONS = {
...
 open: false,           // Open URL in browser on launch.
...

and

// server.js → get server()
...
this._server.on("listening", (e) => {
  this.setupReloadNotifier();
  let { port } = this._server.address();

  let hostsStr = "";
  if(this.options.showAllHosts) {
    // TODO what happens when the cert doesn’t cover non-localhost hosts?
    let hosts = devip().map(host => `${this._serverProtocol}//${host}:${port}${this.options.pathPrefix} or`);
    hostsStr = hosts.join(" ") + " ";
  }

  this.logger.info(`Server at ${hostsStr}${this._serverProtocol}//localhost:${port}${this.options.pathPrefix}${this.options.showVersion ? ` (v${pkg.version})` : ""}`);

  if(this.options.open) {
    this.logger.info(`Opening in browser...`);
    require('out-url').open(`${hostsStr}${this._serverProtocol}//localhost:${port}${this.options.pathPrefix}`);
  }

});


return this._server;
...

But adds a dependency and if you change the open option from true to false in .eleventy.js while the server is running it opens the browser again. I'm sure there is a much better way to do this.

Start in server.js, especially the DEFAULT_OPTIONS definition and the get server() listening handler shown in the issue. Trace how server options are updated while the server runs and determine how the browser should open only when startup requires it. Done means an open option is supported without adding an unnecessary dependency or reopening the browser after the option changes.