diff --git a/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/CreateNew.php b/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/CreateNew.php
index cb57cc489866cbf3e74ee80f51eb49a5b18b2cf7..fef47e90171c5b7191309a4d0d1c108ea9099268 100644
--- a/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/CreateNew.php
+++ b/core/modules/system/src/Plugin/ImageToolkit/Operation/gd/CreateNew.php
@@ -52,7 +52,7 @@ protected function arguments() {
   protected function validateArguments(array $arguments) {
     // Assure extension is supported.
     if (!in_array($arguments['extension'], $this->getToolkit()->getSupportedExtensions())) {
-      throw new \InvalidArgumentException("Invalid extension ('{$arguments['extension']}') specified for the image 'convert' operation");
+      throw new \InvalidArgumentException("Invalid extension ('{$arguments['extension']}') specified for the image 'create_new' operation");
     }
 
     // Assure integers for width and height.