diff --git a/cockatrice/src/interface/card_picture_loader/card_picture_loader_worker_work.h b/cockatrice/src/interface/card_picture_loader/card_picture_loader_worker_work.h
index aa7aed5f4..cdffc1dff 100644
--- a/cockatrice/src/interface/card_picture_loader/card_picture_loader_worker_work.h
+++ b/cockatrice/src/interface/card_picture_loader/card_picture_loader_worker_work.h
@@ -13,6 +13,8 @@
 
 inline Q_LOGGING_CATEGORY(CardPictureLoaderWorkerWorkLog, "card_picture_loader.worker");
 
+class CardPictureLoaderWorker;
+
 /**
  * @class CardPictureLoaderWorkerWork
  * @ingroup PictureLoader