Unbridled Recursion in Settings Config on Save

There is something causing the config for this element to be recursively added to its own settings in the config file. Sometimes it is only a few levels deep and other times it is many levels deep. The recursion happens every time the webform is saved.

Webforms with this problem cannot find the settings, causing this warning in dblog when the form is submitted:

Warning: Undefined array key "right_side" in Drupal\webform_handler_compare_fields\Plugin\WebformHandler\CompareFieldsWebformHandler->compareFields() (line 241 of /var/www/docroot/modules/contrib/webform_handler_compare_fields/src/Plugin/WebformHandler/CompareFieldsWebformHandler.php)

for each of the keys in those settings (left_side, operator, right_side, datatype and errorField).