diff --git a/packages/runtime-core/src/createRenderer.ts b/packages/runtime-core/src/createRenderer.ts
index 33cae409..986667a1 100644
--- a/packages/runtime-core/src/createRenderer.ts
+++ b/packages/runtime-core/src/createRenderer.ts
@@ -512,6 +512,8 @@ export function createRenderer<
       hostInsert(fragmentStartAnchor, container, anchor)
       hostInsert(fragmentEndAnchor, container, anchor)
       // a fragment can only have array children
+      // since they are either generated by the compiler, or implicitly created
+      // from arrays.
       mountChildren(
         n2.children as HostVNodeChildren,
         container,