diff --git a/apps/app/src/components-v2/layout/AppTopbar.vue b/apps/app/src/components-v2/layout/AppTopbar.vue
index acb3118e..729e0c93 100644
--- a/apps/app/src/components-v2/layout/AppTopbar.vue
+++ b/apps/app/src/components-v2/layout/AppTopbar.vue
@@ -324,42 +324,47 @@ const userMenuItems = computed<MenuItem[]>(() => [
         .ws-mobile-btn: display none (>= 1024px). On mobile: display flex.
         38x38, rounded, color #fff, font-bold 12px, gradient bg via inline :style
         (dynamic hex pair — RFC §7.4). Box-shadow via scoped CSS.
+        Plan-3 fix: free sibling in #end flex row — NOT nested inside data-tb="search".
       -->
-      <div data-tb="search">
-        <button
-          v-if="authStore.currentOrganisation"
-          type="button"
-          class="ws-mobile-btn-shadow lg:hidden inline-flex h-[38px] w-[38px] flex-shrink-0 items-center justify-center rounded-[var(--p-border-radius)] border-0 text-[12px] font-bold text-white"
-          :style="{
-            background: `linear-gradient(135deg, ${mobileOrgGradient[0]}, ${mobileOrgGradient[1]})`,
-          }"
-          :aria-label="`Workspace: ${authStore.currentOrganisation.name}`"
-        >
-          {{ mobileOrgInitials }}
-        </button>
+      <button
+        v-if="authStore.currentOrganisation"
+        type="button"
+        class="ws-mobile-btn-shadow lg:hidden inline-flex h-[38px] w-[38px] flex-shrink-0 items-center justify-center rounded-[var(--p-border-radius)] border-0 text-[12px] font-bold text-white"
+        :style="{
+          background: `linear-gradient(135deg, ${mobileOrgGradient[0]}, ${mobileOrgGradient[1]})`,
+        }"
+        :aria-label="`Workspace: ${authStore.currentOrganisation.name}`"
+      >
+        {{ mobileOrgInitials }}
+      </button>
 
-        <!--
-          Search — static chrome, no backend.
-          .search: position relative, w-[320px], max-w-full
-          .search input: h-[38px], px-[12px] ps-[36px], bg-surface-alt, border rounded
-          .search .kbd: absolute right-2, text-[11px], px-[6px] py-[2px], border rounded
-          Hidden on smallest viewports per crewli-starter (<768px: width 0 / display:none)
-        -->
-        <div class="relative hidden sm:block w-[240px] lg:w-[320px] max-w-full">
-          <Icon
-            name="tabler-search"
-            :size="16"
-            class="pointer-events-none absolute left-[11px] top-1/2 -translate-y-1/2 text-[var(--p-text-muted-color)]"
-          />
-          <InputText
-            class="h-[38px] w-full rounded-[var(--p-border-radius)] border border-transparent bg-[var(--p-content-hover-background)] ps-[36px] pe-[52px] text-[var(--p-text-color)] placeholder:text-[var(--p-text-muted-color)] focus:border-[var(--p-primary-color)] focus:bg-[var(--p-content-background)] focus:shadow-[0_0_0_3px_var(--p-primary-50)] focus:outline-none transition-[border-color,background,box-shadow] duration-150"
-            placeholder="Search artists, crew, events..."
-            :pt="{ root: { 'data-search-input': '' } }"
-          />
-          <span class="pointer-events-none absolute right-2 top-1/2 -translate-y-1/2 rounded-[var(--p-border-radius-sm,4px)] border border-[var(--p-content-border-color)] bg-[var(--p-content-background)] px-[6px] py-[2px] font-mono text-[11px] text-[var(--p-text-muted-color)]">
-            ⌘K
-          </span>
-        </div>
+      <!--
+        Search — static chrome, no backend.
+        data-tb="search" carries the original layout classes of the search block
+        so flex participation is identical to Plan-2 (direct #end flex child with
+        relative + hidden sm:block + width). No inner wrapper div needed.
+        .search: position relative, w-[240px] sm / w-[320px] lg, max-w-full
+        .search input: h-[38px], px-[12px] ps-[36px], bg-surface-alt, border rounded
+        .search .kbd: absolute right-2, text-[11px], px-[6px] py-[2px], border rounded
+        Hidden on smallest viewports per crewli-starter (<768px: width 0 / display:none)
+      -->
+      <div
+        data-tb="search"
+        class="relative hidden sm:block w-[240px] lg:w-[320px] max-w-full"
+      >
+        <Icon
+          name="tabler-search"
+          :size="16"
+          class="pointer-events-none absolute left-[11px] top-1/2 -translate-y-1/2 text-[var(--p-text-muted-color)]"
+        />
+        <InputText
+          class="h-[38px] w-full rounded-[var(--p-border-radius)] border border-transparent bg-[var(--p-content-hover-background)] ps-[36px] pe-[52px] text-[var(--p-text-color)] placeholder:text-[var(--p-text-muted-color)] focus:border-[var(--p-primary-color)] focus:bg-[var(--p-content-background)] focus:shadow-[0_0_0_3px_var(--p-primary-50)] focus:outline-none transition-[border-color,background,box-shadow] duration-150"
+          placeholder="Search artists, crew, events..."
+          :pt="{ root: { 'data-search-input': '' } }"
+        />
+        <span class="pointer-events-none absolute right-2 top-1/2 -translate-y-1/2 rounded-[var(--p-border-radius-sm,4px)] border border-[var(--p-content-border-color)] bg-[var(--p-content-background)] px-[6px] py-[2px] font-mono text-[11px] text-[var(--p-text-muted-color)]">
+          ⌘K
+        </span>
       </div>
 
       <!--
diff --git a/apps/app/src/components-v2/layout/__tests__/AppTopbar.spec.ts b/apps/app/src/components-v2/layout/__tests__/AppTopbar.spec.ts
index 56213b0b..aefb87ee 100644
--- a/apps/app/src/components-v2/layout/__tests__/AppTopbar.spec.ts
+++ b/apps/app/src/components-v2/layout/__tests__/AppTopbar.spec.ts
@@ -309,11 +309,49 @@ describe('AppTopbar', () => {
     expect(w.findComponent(MenubarStub).exists()).toBe(true)
   })
 
-  it('breadcrumb lives in Menubar #start, user cluster in #end', () => {
+  it('breadcrumb lives in Menubar #start, user cluster in #end; search wrapper exists and mobile-ws-btn is NOT its descendant', async () => {
+    // Mount first so the component's pinia plugin is active, then get the
+    // store instance from that same pinia context.
     const w = mountTopbar()
     const bar = w.findComponent(MenubarStub)
 
     expect(bar.find('[data-tb="breadcrumb"]').exists()).toBe(true)
     expect(bar.find('[data-tb="user"]').exists()).toBe(true)
+
+    // AD-3 regression lock: data-tb="search" must exist as a direct #end sibling
+    expect(bar.find('[data-tb="search"]').exists()).toBe(true)
+
+    // Seed authStore with an organisation so authStore.currentOrganisation resolves
+    // (it is a computed derived from organisations[0]).  setUser() is the public API
+    // that populates the organisations array.
+    // Must call useAuthStore() AFTER mountTopbar() so we use the same pinia instance.
+    const authStore = useAuthStore()
+
+    authStore.setUser({
+      id: 'u1',
+      first_name: 'Test',
+      last_name: 'User',
+      full_name: 'Test User',
+      date_of_birth: null,
+      email: 'test@example.com',
+      phone: null,
+      timezone: 'UTC',
+      locale: 'en',
+      avatar: null,
+      organisations: [{ id: 'org-1', name: 'Test Org', slug: 'test-org', role: 'org_admin' }],
+      app_roles: [],
+      permissions: [],
+    })
+
+    await w.vm.$nextTick()
+
+    const wsBtnSelector = 'button[aria-label^="Workspace:"]'
+
+    // The mobile workspace button must exist in the bar (currentOrganisation is set).
+    expect(bar.find(wsBtnSelector).exists()).toBe(true)
+
+    // The mobile workspace button must NOT be a descendant of data-tb="search".
+    // In the corrected structure it is a free sibling in the #end flex row.
+    expect(bar.find('[data-tb="search"]').find(wsBtnSelector).exists()).toBe(false)
   })
 })