diff --git a/modules/salesforce_webform/src/Plugin/SalesforceMappingField/WebformElements.php b/modules/salesforce_webform/src/Plugin/SalesforceMappingField/WebformElements.php
index 48557540e3772948468ad92c0ff6621a7d769ad6..ce994226e865c9fe31ce7fc5d4bff3def6724ad4 100644
--- a/modules/salesforce_webform/src/Plugin/SalesforceMappingField/WebformElements.php
+++ b/modules/salesforce_webform/src/Plugin/SalesforceMappingField/WebformElements.php
@@ -108,7 +108,7 @@ class WebformElements extends SalesforceMappingFieldPluginBase {
    */
   public function getPluginDefinition() {
     $definition = parent::getPluginDefinition();
-    $element_parts = explode('__', $this->config('drupal_field_value'));
+    $element_parts = explode('__', (string) $this->config('drupal_field_value'));
     $main_element_name = reset($element_parts);
     $webform = $this->entityTypeManager->getStorage('webform')->load($this->mapping->get('drupal_bundle'));
     // Unfortunately, the best we can do for webform dependencies is a single