Custom Body Class triggers PHP 8.2 warning: Deprecated function: preg_match(): Passing null to parameter #2

I've applied the attached patch and tested this. The reported warning is no longer triggered.
Marking this as RTBC.

I'm using drupal 10.3.1 and recently installed the Custom Body Class module ( https://www.drupal.org/project/custom_body_class → )

I am still getting the error below even after applying the patch ( https://www.drupal.org/project/custom_body_class/issues/3436902 🐛 Custom Body Class triggers PHP 8.2 warning: Deprecated function: preg_match(): Passing null to parameter #2 RTBC ) whenever I try to add a custom class to the body of various content types.

ERROR: Deprecated function: preg_match(): Passing null to parameter #2 ($subject) of type string is deprecated in custom_body_class_node_special_character_form_validate() (line 121 of modules/contrib/custom_body_class/custom_body_class.module).

I test patch PHP 8.1.20 and Drupal 10.3.1
and error is no longer.

Patch worked for me.