Drupal\Core\File\Exception\InvalidStreamWrapperException: in Drupal\Core\File\FileUrlGenerator->doGenerateString() (line 106 of /docroot/core/lib/Drupal/Core/File/FileUrlGenerator.php)

I also struggled with this same problem, after upgrading from drupal 7 to drupal 9.52. Any idea how to solve this problem?

Provide the information I requested on comment #8.

Thanks for response, the extended information is:
Drupal\Core\File\Exception\InvalidStreamWrapperException: private://logo.png in Drupal\Core\File\FileUrlGenerator->doGenerateString() (line 112 of core/lib/Drupal/Core/File/FileUrlGenerator.php).

I was having this problem. Solved by properly setting up the private file system in settings.php with

$settings['file_private_path'] = '../someplace';

Details that may be related: I was moving a site and setting up s3fs at the same time. I had moved all the private:// stuff to S3. As with grzegorz the $uri causing the exception was private://bla_bla_bla. Once I made a private_files directory and pointed to it in settings.php, and cleared the caches, I got these messages:

* Warning: file_exists(): Unable to find the wrapper "private" - did you forget to enable it when you configured PHP? in Drupal\Component\FileSecurity\FileSecurity::writeFile() (line 155 of core/lib/Drupal/Component/FileSecurity/FileSecurity.php).

* Warning: file_exists(): Unable to find the wrapper "private" - did you forget to enable it when you configured PHP? in system_requirements() (line 714 of core/modules/system/system.install).

They appeared once. When I went to /admin/config/media/file-system I saw the 'Private file system path' I had set up, and these exceptions had cleared, and the S3 private files were working.

I faced the same issue I Fixed it by adding this on settings.php
$settings['file_private_path'] = '../private/files';

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