diff --git a/packages/ui/src/lib/components/RoomyThread.svelte b/packages/ui/src/lib/components/RoomyThread.svelte
index 08dfe5e..f584a6b 100644
--- a/packages/ui/src/lib/components/RoomyThread.svelte
+++ b/packages/ui/src/lib/components/RoomyThread.svelte
@@ -143,6 +143,9 @@
         ? selected.filter((id) => id !== target.id)
         : [...selected, target.id]
     }
+    if (event.currentTarget instanceof HTMLInputElement) {
+      event.currentTarget.checked = selected.includes(target.id)
+    }
     anchor = index
   }
 
diff --git a/packages/ui/src/lib/components/RoomyThread.svelte.test.ts b/packages/ui/src/lib/components/RoomyThread.svelte.test.ts
index fc1b92a..6554660 100644
--- a/packages/ui/src/lib/components/RoomyThread.svelte.test.ts
+++ b/packages/ui/src/lib/components/RoomyThread.svelte.test.ts
@@ -152,6 +152,10 @@ describe('Roomy thread', () => {
     flushSync()
     expect(boxes.map((box) => box.checked)).toEqual([false, true, true, true, false])
     expect(target.querySelector('.rmy-foot')?.textContent).toContain('3 selected')
+    boxes[2]?.dispatchEvent(new MouseEvent('click', { bubbles: true, cancelable: true, shiftKey: true }))
+    flushSync()
+    expect(boxes.map((box) => box.checked)).toEqual([false, true, true, true, false])
+    expect(target.querySelector('.rmy-foot')?.textContent).toContain('3 selected')
 
     const importer = target.querySelector('.rmy-acts .btn-p') as HTMLButtonElement
     // The phrase is held to the count by a non-breaking space; below 560px the phrase is what goes.