1 files changed, 6 insertions, 0 deletions
diff --git a/source/blender/windowmanager/WM_types.h b/source/blender/windowmanager/WM_types.h
index 24aa5bc4869..d40c0715a09 100644
--- a/source/blender/windowmanager/WM_types.h
+++ b/source/blender/windowmanager/WM_types.h
@@ -904,6 +904,12 @@ typedef struct wmDropBox {
   void (*copy)(struct wmDrag *, struct wmDropBox *);
 
   /**
+   * If the operator is cancelled (returns `OPERATOR_CANCELLED`), this can be used for cleanup of
+   * `copy()` resources.
+   */
+  void (*cancel)(struct Main *, struct wmDrag *, struct wmDropBox *);
+
+  /**
    * If poll succeeds, operator is called.
    * Not saved in file, so can be pointer.
    */