Private files doesn't work after uprgade to Drupal 10.3 when admin_routes is true

On our site we have this module enabled - latest 2.0.1 version.
Detection method Administration language for Interface text language detection is first in the list.
Option Returns particular language on admin routes is Enabled

Running on Drupal 10.2.7 I can access private files (/system/files/...)
After upgrade to Drupal 10.3.0 I can't download such files - error Page not found

It seems that is is related to the update introduced in the drupal 10.3.0-rc1 release https://www.drupal.org/project/drupal/releases/10.3.0-rc1 → :
Issue #3085360 by bradjones1, josephdpurcell, Giuseppe87, ravi.shankar, rajandro, ridhimaabrol24, bbrala, andregp, jhedstrom: RouteProvider::getRouteCollectionForRequest() can poison query string of next request
https://git.drupalcode.org/project/drupal/-/commit/fbe023ba6ddbf719ee8d4...

If I remove update introduced in core/lib/Drupal/Core/Routing/RouteProvider.php then file download works again.

Could you please check?

Thanks