chore: add comment

Author: YousefED

packages/core/src/schema/blocks/createSpec.ts

@@ -210,6 +210,8 @@ export function addNodeAndExtensionsToSpec<
 
           // See explanation for why `update` is not implemented for NodeViews
           // https://github.com/TypeCellOS/BlockNote/pull/1904#discussion_r2313461464
+          // TODO: in a future version, we might want to implement updates so that
+          // vanilla blocks don't always re-render entirely (https://github.com/TypeCellOS/BlockNote/issues/220)
           return nodeView;
         };
       },