@@ -0,0 +1,22 @@
+---
+'@object-ui/plugin-detail': patch
+---
+
+fix(plugin-detail): a related list's `list_toolbar` action authored `visible: false` is hidden
+
+`RelatedToolbarButton` decided whether an action declared a `visible` gate by
+truthiness. A literal `visible: false`, the most explicit way an author can say
+"never show this", is falsy, so the gate was skipped and the header button
+rendered for everyone. It now asks the question with `hasDeclaredVisibilityGate`,
+the one definition the rest of the action family already uses (objectui#3812):
+
+- `visible: false` hides the button.
+- A blank predicate (`''`, or a whitespace-only string) is no gate, so the button
+  shows. A whitespace-only `visible` used to hide the button; it now shows, as it
+  does on every other action surface.
+- A CEL string is evaluated, as before.
+- A predicate that faults still hides the button and is reported once
+  (objectui#11212), unchanged.
+
+The server still judges the action's permission when it runs; this is the
+presentation gate.
@@ -25,6 +25,7 @@ import {
   AlertDialogTitle,
   cn,
   EmptyValue,
+  hasDeclaredVisibilityGate,
   resolveIcon,
   useIsMobile,
 } from '@object-ui/components';
@@ -435,6 +436,11 @@ function dropRedactedColumns<T>(cols: T[], redacted: ReadonlySet<string>): T[] {
  * permissions payload has loaded, an unbound root — hides the button and is
  * reported once, instead of showing an action whose guard is broken. This leg
  * used to fail SOFT to `true`.
+ *
+ * Whether a gate is DECLARED at all is asked with `hasDeclaredVisibilityGate`,
+ * as every other member of the action family asks it (objectui#3812,
+ * objectui#11244), never by truthiness: `visible: false` is a declared gate and
+ * hides the button, while a blank predicate (`''`, whitespace) is no gate.
  */
 export const RelatedToolbarButton: React.FC<{
   action: RelatedRowActionDef;
@@ -447,7 +453,7 @@ export const RelatedToolbarButton: React.FC<{
     throwOnError: true,
     label: `related-list toolbar action "${action.name}" (visible)`,
   });
-  if (visiblePred && !isVisible) return null;
+  if (hasDeclaredVisibilityGate(visiblePred) && !isVisible) return null;
   const ActionIcon = action.icon ? resolveIconComponent(action.icon) : null;
   return (
     <Button
 
@@ -115,3 +115,49 @@ describe('RelatedList list_toolbar button — a faulting `visible` hides (object
     }
   });
 });
+
+/**
+ * objectui#11244 — whether a `visible` gate is DECLARED is asked with
+ * `hasDeclaredVisibilityGate`, as the rest of the action family asks it
+ * (objectui#3812), never by truthiness. A literal `visible: false` — the most
+ * explicit way an author can say "never show this" — is falsy, so a truthiness
+ * test read it as "no gate" and the button rendered for everyone. A blank
+ * predicate is still no gate (the action shows), and a CEL string is evaluated.
+ * The fail-closed leg on a FAULT is the objectui#11212 block above, unchanged.
+ */
+describe('RelatedList list_toolbar button — a declared `visible` is asked by declaredness, not truthiness (objectui#11244)', () => {
+  it('hides a toolbar action authored `visible: false` (DETECTOR)', () => {
+    renderButton({ name: 'archive_11244', label: 'Archive', visible: false });
+    renderButton({ name: 'export', label: 'Export' });
+    expect(screen.getByTestId('related-toolbar-action-export')).toBeInTheDocument();
+    expect(screen.queryByTestId('related-toolbar-action-archive_11244')).toBeNull();
+  });
+
+  it('shows a toolbar action authored `visible: true`', () => {
+    renderButton({ name: 'archive_11244', label: 'Archive', visible: true });
+    expect(screen.getByTestId('related-toolbar-action-archive_11244')).toBeInTheDocument();
+  });
+
+  it.each([
+    ['an empty string', ''],
+    ['a whitespace-only string', '   '],
+  ])('reads a blank `visible` (%s) as no gate, so the action shows', (_label, blank) => {
+    const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+    try {
+      renderButton({ name: 'archive_11244', label: 'Archive', visible: blank });
+      expect(screen.getByTestId('related-toolbar-action-archive_11244')).toBeInTheDocument();
+    } finally {
+      warn.mockRestore();
+    }
+  });
+
+  it('evaluates a CEL string `visible` that answers true: the action shows', () => {
+    renderButton({ name: 'archive_11244', label: 'Archive', visible: '1 == 1' });
+    expect(screen.getByTestId('related-toolbar-action-archive_11244')).toBeInTheDocument();
+  });
+
+  it('evaluates a CEL string `visible` that answers false: the action hides', () => {
+    renderButton({ name: 'archive_11244', label: 'Archive', visible: '1 == 2' });
+    expect(screen.queryByTestId('related-toolbar-action-archive_11244')).toBeNull();
+  });
+});