Fatal error version 1.9

Update to version 1.9 generates a fatal error. I’ve changed the root of my URL for […]
It was ok up to version 1.8.1
Here is the error from wl-cli

Fatal error: Uncaught Error: Class 'JoostBlog\WP\Comment\Inc\Hacks' not found in [...]wp-content/plugins/yoast-comment-hacks/yoast-comment-hacks.php:53
Stack trace:                                                                                                                         
#0 [...]wp-settings.php(428): include_once()            
#1 phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Runner.php(1336): require('[...]/w...')                          
#2 phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Runner.php(1254): WP_CLI\Runner->load_wordpress()
#3 phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/WP_CLI/Bootstrap/LaunchRunner.php(28): WP_CLI\Runner->start()                   
#4 phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/bootstrap.php(78): WP_CLI\Bootstrap\LaunchRunner->process()                     
#5 phar:///usr/local/bin/wp/vendor/wp-cli/wp-cli/php/wp-cli.php(32): WP_CLI\bootstrap()                                              
#6 phar:///usr/local/bin/wp/php/boot-phar.php(11): include('phar:///usr/loc...')                                                     
#7 /usr/local/bin/wp(4): include('phar:///usr/loc...')                                                                               
#8 {main}                                                                                                                            
  thrown in [...]wp-content/plugins/yoast-comment-hacks/yoast-comment-hacks.php on line 53