Pro Search - Deprecation errors

[ic360-com]

I'm seeing multiples of the following Deprecation error on the Pro Search results page:

Deprecated
preg_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated
ee/ExpressionEngine/Addons/pro_search/libraries/Pro_search_words.php, line 333
Severity: E_DEPRECATED

These only appeared when the I added the keywords:inflect="yes" parameter to the {exp:pro_search:results} tag.

EE 7.4.11
PHP 8.2