Drupal

Error

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TypeError: array_keys(): Argument #1 ($array) must be of type array, null given in array_keys() (line 70 of core/lib/Drupal/Core/Extension/ThemeHandler.php).
array_keys() (Line: 70)
Drupal\Core\Extension\ThemeHandler->listInfo() (Line: 61)
_drupal_maintenance_theme() (Line: 324)
drupal_maintenance_theme() (Line: 519)
install_begin_request() (Line: 118)
install_drupal() (Line: 53)