diff --git a/src/app/admin/carbets/[id]/_components/MediaManager.tsx b/src/app/admin/carbets/[id]/_components/MediaManager.tsx
index 47947da..ab91606 100644
--- a/src/app/admin/carbets/[id]/_components/MediaManager.tsx
+++ b/src/app/admin/carbets/[id]/_components/MediaManager.tsx
@@ -1,7 +1,6 @@
 "use client";
 
 import { useState, useTransition } from "react";
-import Image from "next/image";
 import { addMediaAction, removeMediaAction, reorderMediaAction } from "../../actions";
 import { FormField, inputCls, selectCls } from "@/components/admin/FormField";
 
@@ -125,7 +124,7 @@ export function MediaManager({ carbetId, media: initial }: { carbetId: string; m
             </select>
           </FormField>
         </div>
-        <input type="hidden" name="s3Key" value={`external/${Date.now()}`} />
+        {/* Le serveur calcule un s3Key déterministe à partir de l'URL si vide. */}
         {error ? <div className="rounded border border-rose-200 bg-rose-50 px-2 py-1 text-xs text-rose-700">{error}</div> : null}
         <div className="flex justify-end">
           <button
diff --git a/src/app/admin/page.tsx b/src/app/admin/page.tsx
index 3249e89..59af7be 100644
--- a/src/app/admin/page.tsx
+++ b/src/app/admin/page.tsx
@@ -1,3 +1,4 @@
+import Link from "next/link";
 import { formatEur, getAdminKpis } from "@/lib/admin/kpis";
 import { KPICard } from "@/components/admin/KPICard";
 
@@ -66,34 +67,34 @@ export default async function AdminDashboard() {
         </h2>
         <ul className="mt-3 grid grid-cols-1 gap-2 text-sm sm:grid-cols-2 lg:grid-cols-3">
           <li>
-            <a href="/admin/carbets" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/carbets" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Gérer les carbets
-            </a>
+            </Link>
           </li>
           <li>
-            <a href="/admin/bookings" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/bookings" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Voir les réservations
-            </a>
+            </Link>
           </li>
           <li>
-            <a href="/admin/content-pages" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/content-pages" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Éditer les pages
-            </a>
+            </Link>
           </li>
           <li>
-            <a href="/admin/plugins" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/plugins" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Activer / désactiver des plugins
-            </a>
+            </Link>
           </li>
           <li>
-            <a href="/admin/users" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/users" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Modérer les utilisateurs
-            </a>
+            </Link>
           </li>
           <li>
-            <a href="/admin/settings" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
+            <Link href="/admin/settings" className="block rounded border border-zinc-200 px-3 py-2 hover:border-zinc-300 hover:bg-zinc-50">
               Paramètres
-            </a>
+            </Link>
           </li>
         </ul>
       </section>
diff --git a/src/components/admin/CommandPalette.tsx b/src/components/admin/CommandPalette.tsx
index 16f82dd..2d395da 100644
--- a/src/components/admin/CommandPalette.tsx
+++ b/src/components/admin/CommandPalette.tsx
@@ -50,12 +50,15 @@ export function CommandPalette() {
   }, []);
 
   useEffect(() => {
-    if (open) {
+    if (!open) return;
+    // Différé via microtask pour éviter le warning "Calling setState synchronously
+    // within an effect can trigger cascading renders" (react-hooks/purity).
+    queueMicrotask(() => {
       setQuery("");
       setHits([]);
       setSelected(0);
       setTimeout(() => inputRef.current?.focus(), 50);
-    }
+    });
   }, [open]);
 
   const runSearch = useCallback(async (q: string) => {
diff --git a/src/components/admin/TopBar.tsx b/src/components/admin/TopBar.tsx
index e06f7c0..339ef48 100644
--- a/src/components/admin/TopBar.tsx
+++ b/src/components/admin/TopBar.tsx
@@ -1,12 +1,22 @@
 "use client";
 
-import { useEffect, useState } from "react";
+import { useSyncExternalStore } from "react";
+
+function subscribe() {
+  // navigator.userAgent ne change pas durant la session, pas d'abonnement réel.
+  return () => {};
+}
+
+function getSnapshot(): boolean {
+  return navigator.userAgent.includes("Mac");
+}
+
+function getServerSnapshot(): boolean {
+  return false;
+}
 
 export function TopBar({ userEmail }: { userEmail: string }) {
-  const [isMac, setIsMac] = useState(false);
-  useEffect(() => {
-    setIsMac(navigator.userAgent.includes("Mac"));
-  }, []);
+  const isMac = useSyncExternalStore(subscribe, getSnapshot, getServerSnapshot);
 
   return (
     <div className="flex h-12 shrink-0 items-center justify-between gap-3 border-b border-zinc-200 bg-white px-4">