In some cases when clearing the cache, I got this error:

TypeError {#7873
  #message: "array_keys(): Argument #1 ($array) must be of type array, bool given"
  #code: 0
  #file: "/app/vendor/jane-php/automapper-bundle/CacheWarmup/CacheWarmer.php"
  #line: 55
  trace: {
    /app/vendor/jane-php/automapper-bundle/CacheWarmup/CacheWarmer.php:55 { …}

so require_once returns a bool although the file do exist (there is a check just above) and I've check that even when the error occurs, the file's content is OK. So I concluded that the file has already been required (but I have to confess that I don't know why 🤷 ) and using require instead fixes the problem

check https://3v4l.org/5fadP#v8.2.7 => the second require_once returns true