Anonymous Publishing CL WSOD on /node/add page for anonymous users

Problem/Motivation

Running Drupal 10.1.6

Following error is reported:

Drupal\Core\Security\UntrustedCallbackException: Render #post_render callbacks must be methods of a class that implements \Drupal\Core\Security\TrustedCallbackInterface or be an anonymous function. The callback was anonymous_publishing_honeyfield_cl_post_render. See https://www.drupal.org/node/2966725 → in Drupal\Core\Render\Renderer->doTrustedCallback() (line 106 of core/lib/Drupal/Core/Security/DoTrustedCallbackTrait.php).

Authenticated users are not affected.

Steps to reproduce

1. Enable full error reporting.
2. In Main settings, enable anonymous publishing for Article.
3. Navigate to /node/add/article.
4. Inspect WSOD.