PHP 8.1 compatibility - deprecated function preg_replace passing null to parameter 3

Until a new tag is released, use dev build instead, composer override
composer require drupal/xnttfiles:'1.0.x@dev as 1.0.2-beta2'

see patch

new patch

What about/could you try:

$struct_re = $structure ?? $this->configuration['structure'] ?? '';

(instead of

$struct_re = $structure ?? $this->configuration['structure'];
$struct_re = is_null($struct_re) ?? '' : $struct_re;

)

In fact, that bug was fixed 6 month ago by commit 3935df26 but there was no tagged release. Reopen the issue if you consider the problem is still there with beta 3.

Automatically closed - issue fixed for 2 weeks with no activity.