cleanup comment

apps/app/src/client/components/RevisionComparer/RevisionComparer.tsx

@@ -1,4 +1,4 @@
-import React, { type JSX, useState } from 'react';
+import { type JSX, useState } from 'react';
 import dynamic from 'next/dynamic';
 import type { IRevisionHasId } from '@growi/core';
 import { pagePathUtils } from '@growi/core/dist/utils';
@@ -11,8 +11,9 @@ import {
   DropdownToggle,
 } from 'reactstrap';
 
-// diff2html is a large library used only for interactive diff viewing (no SSR content).
-// Loading it client-only keeps it out of .next/node_modules/ so it can stay in devDependencies.
+// diff2html is a large library used only for interactive diff viewing.
+// ssr: false skips server-side rendering for performance; the package itself must
+// stay in dependencies because Turbopack still externalises it via static import analysis.
 const RevisionDiff = dynamic(
   () => import('../PageHistory/RevisionDiff').then((mod) => mod.RevisionDiff),
   { ssr: false },