Statistics
The Statistics module was deprecated in Drupal 10 and removed in Drupal 11. If your site is using the Statistics module, you need to install the contributed Statistics project.
The default .htaccess file changed to remove support for the Statistics module. The htaccess protection is now supplied by the contributed project. Sites using a custom .htaccess file should ensure that the rule, shown below, is removed from their own copy of the file.
# Allow access to Statistics module's custom front controller.
# Copy and adapt this rule to directly execute PHP files in contributed or
# custom modules or to run another PHP application in the same directory.
RewriteCond %{REQUEST_URI} !/core/modules/statistics/statistics\.php$