diff --git a/surfsense_web/components/assistant-ui/thread.tsx b/surfsense_web/components/assistant-ui/thread.tsx
index 24f070b4e..c4f6fed05 100644
--- a/surfsense_web/components/assistant-ui/thread.tsx
+++ b/surfsense_web/components/assistant-ui/thread.tsx
@@ -479,14 +479,14 @@ const Composer: FC = () => {
 	}, [isDesktop, showDocumentPopover, showPromptPicker, threadId]);
 
 	// Close document picker when a sidebar slide-out panel (inbox, etc.) opens.
+	// React only on changes to the tick — comparing against the previously-seen
+	// value preserves the one-shot semantics of the prior window-event approach
+	// (no retroactive close on mount if a panel had already opened earlier).
 	const slideoutOpenedTick = useAtomValue(slideoutOpenedTickAtom);
-	const isFirstSlideoutTickRef = useRef(true);
+	const lastSeenSlideoutTickRef = useRef(slideoutOpenedTick);
 	useEffect(() => {
-		void slideoutOpenedTick;
-		if (isFirstSlideoutTickRef.current) {
-			isFirstSlideoutTickRef.current = false;
-			return;
-		}
+		if (lastSeenSlideoutTickRef.current === slideoutOpenedTick) return;
+		lastSeenSlideoutTickRef.current = slideoutOpenedTick;
 		setShowDocumentPopover(false);
 		setMentionQuery("");
 	}, [slideoutOpenedTick]);
diff --git a/surfsense_web/lib/layout-events.ts b/surfsense_web/lib/layout-events.ts
index 27ea8de39..755329c41 100644
--- a/surfsense_web/lib/layout-events.ts
+++ b/surfsense_web/lib/layout-events.ts
@@ -2,8 +2,10 @@ import { atom } from "jotai";
 
 /**
  * Tick counter that increments each time a sidebar slide-out panel opens.
- * Consumers read this with `useAtomValue` and react to it changing — guard
- * the initial render with a ref so the effect only fires on subsequent
- * opens, matching the one-shot semantics of the previous window event.
+ * Consumers read this with `useAtomValue` and store the last-seen value in
+ * a ref so the effect fires only when the tick changes. This preserves the
+ * one-shot semantics of the previous window-event implementation: a
+ * subscriber that mounts after a panel has already opened does not
+ * retroactively re-trigger.
  */
 export const slideoutOpenedTickAtom = atom(0);