diff --git a/web/src/lib/components/layout/FolderTree.svelte b/web/src/lib/components/layout/FolderTree.svelte
index f7de61d..15b7701 100644
--- a/web/src/lib/components/layout/FolderTree.svelte
+++ b/web/src/lib/components/layout/FolderTree.svelte
@@ -40,6 +40,7 @@
 <script lang="ts">
 	import { filters } from '$lib/stores/filters.svelte';
 	import { browser } from '$app/environment';
+	import { untrack } from 'svelte';
 	import { FolderPlus, Pencil, Trash2 } from 'lucide-svelte';
 	import Self from './FolderTree.svelte';
 	import KebabMenu, { Item, Separator } from './KebabMenu.svelte';
@@ -105,6 +106,37 @@
 		if (selectedPath !== undefined) return selectedPath === path;
 		return filters.folderPath === path;
 	}
+
+	// Auto-expand the ancestor chain of the active folder so the
+	// highlighted row is actually visible after a deep-link navigation
+	// (RightSidebar's open-folder icon, URL hydration, etc.). Each
+	// FolderTree instance only owns the openSet entries for the nodes
+	// rendered at its depth, but since the root instance expands the
+	// top-level ancestor first, the child instance for that subtree is
+	// then mounted and runs the same effect — the cascade naturally
+	// reaches the leaf. Skipped in `readonly` mode (the heap-convert
+	// picker has its own selectedPath and shouldn't drive the sidebar
+	// state). Skipped for top-level paths (nothing to expand).
+	$effect(() => {
+		if (readonly || !browser) return;
+		const fp = selectedPath ?? filters.folderPath;
+		if (!fp || fp === '/' || !fp.includes('/')) return;
+		untrack(() => {
+			const parts = fp.split('/');
+			let changed = false;
+			for (let i = 1; i < parts.length; i++) {
+				const ancestor = parts.slice(0, i).join('/');
+				if (ancestor && !openSet.has(ancestor)) {
+					openSet.add(ancestor);
+					changed = true;
+				}
+			}
+			if (changed) {
+				openSet = new Set(openSet);
+				persist();
+			}
+		});
+	});
 </script>
 
 <ul>