diff --git a/apps/mana/apps/web/src/routes/offline/+page.ts b/apps/mana/apps/web/src/routes/offline/+page.ts
index 1b7861cd8..5990bac06 100644
--- a/apps/mana/apps/web/src/routes/offline/+page.ts
+++ b/apps/mana/apps/web/src/routes/offline/+page.ts
@@ -1,10 +1,16 @@
-// FIXME: prerender is disabled because the SvelteKit prerender worker
-// throws "Error: 500 /offline" with no usable stack trace during the
-// production build. Suspected cause: a module-level side-effect on the
-// shared layout (vault-client? data-layer-listeners?) that fails when
-// no `window` is available. SSR'ing the offline page at request time
-// is harmless — it's a static "you're offline" message — but the real
-// fix is to find which import throws on the bare server and guard it.
+// `/offline` ist die Workbox-navigate-fallback. Zwei Dinge sind nötig:
 //
-// First observed: 2026-04-07 during Memoro recording pipeline deploy.
-export const prerender = false;
+// 1. `prerender = true` — sonst landet die Page nicht in
+//    `prerendered/offline.html`, und der @mana/shared-pwa-Workbox-Config
+//    matched nur `**/*.html`. Ohne wirft Workbox beim SW-Register
+//    `non-precached-url: /offline`.
+//
+// 2. Die Page lebt unter `+page@.svelte` (statt `+page.svelte`) — die
+//    `@`-Notation bricht aus der Layout-Chain aus. Das Root-Layout
+//    zieht Dexie / encryption-vault / data-layer-listeners / auth-store
+//    rein; beim Build-SSR throw't Browser-Code (window/document/
+//    indexedDB). Genau das war der „Error: 500 /offline"-Crash, der
+//    2026-04-07 zum prerender=false-FIXME geführt hatte. Mit @-Suffix
+//    hängt die Page direkt am SvelteKit-Root, kein Eltern-Layout — die
+//    OfflinePage aus @mana/shared-ui kommt ohne Stores aus.
+export const prerender = true;