code: private function openBrowser($url)
      {
          $url = ProcessExecutor::escape($url);
  
          $process = new ProcessExecutor($this->getIO());
          if (Platform::isWindows()) {
              return $process->execute('start "web" explorer "' . $url . '"', $output);
          }
  
          $linux = $process->execute('which xdg-open', $output);
          $osx = $process->execute('which open', $output);
  
          if (0 === $linux) {
              $process->execute('xdg-open ' . $url, $output);
          } elseif (0 === $osx) {
              $process->execute('open ' . $url, $output);
          } else {
              $this->getIO()->writeError('No suitable browser opening command found, open yourself: ' . $url);
          }
      }
docs: opens a url in your system default browser
  
  @param string $url