diff --git a/ui/client-app/src/components/FileSystemNavigator.js b/ui/client-app/src/components/FileSystemNavigator.js
index c01bf20..8677aa0 100644
--- a/ui/client-app/src/components/FileSystemNavigator.js
+++ b/ui/client-app/src/components/FileSystemNavigator.js
@@ -59,18 +59,23 @@
     const toggleFolder = async (path) => {
         const isExpanded = expanded[path];
         if (!isExpanded) {
-            // Loading child depth...
-            try {
-                const children = await fetchLevel(path);
-                setExpanded(prev => ({ ...prev, [path]: true }));
-                // Merge children into tree (prevent duplicates)
-                setTree(prev => {
-                    const existingPaths = new Set(prev.map(f => f.path));
-                    const newOnes = children.filter(c => !existingPaths.has(c.path));
-                    return [...prev, ...newOnes];
-                });
-            } catch (err) {
-                setError(`Failed to open folder: ${err.message}`);
+            setExpanded(prev => ({ ...prev, [path]: true }));
+            // Only fetch if we don't already have children for this path in our flat tree
+            // A child would have a path like "path/filename" or "/path/filename"
+            const prefix = path === "/" ? "/" : (path.endsWith("/") ? path : path + "/");
+            const hasChildren = tree.some(node => node.path.startsWith(prefix) && node.path !== path);
+
+            if (!hasChildren) {
+                try {
+                    const children = await fetchLevel(path === "/" ? "." : path);
+                    setTree(prev => {
+                        const existingPaths = new Set(prev.map(f => f.path));
+                        const newOnes = children.filter(c => !existingPaths.has(c.path));
+                        return [...prev, ...newOnes];
+                    });
+                } catch (err) {
+                    setError(`Failed to open folder: ${err.message}`);
+                }
             }
         } else {
             setExpanded(prev => ({ ...prev, [path]: false }));
@@ -148,20 +153,22 @@
     // Helper to render tree recursively
     // Helper to render tree recursively
     const renderSubTree = (currentPath, depth = 0) => {
-        // Find children of this path
+        // Normalize currentPath for filtering
         const children = tree.filter(node => {
-            if (currentPath === initialPath || currentPath === "." || currentPath === "") {
-                const prefix = initialPath === "." || initialPath === "" ? "" : (initialPath.endsWith("/") ? initialPath : initialPath + "/");
-                if (!node.path.startsWith(prefix)) return false;
-                if (node.path === initialPath) return false;
-                const sub = node.path.slice(prefix.length);
-                return !sub.includes("/");
-            } else {
-                const prefix = currentPath.endsWith("/") ? currentPath : currentPath + "/";
-                if (!node.path.startsWith(prefix)) return false;
-                const sub = node.path.slice(prefix.length);
-                return !sub.includes("/");
+            // Special handling for root "/"
+            if (currentPath === "/" || currentPath === initialPath) {
+                // If it's a top-level node, it shouldn't contain more slashes than the root path
+                const rel = node.path.startsWith("/") ? node.path.slice(1) : node.path;
+                return !rel.includes("/");
             }
+
+            // For nested folders, a child is anything that starts with "currentPath/" and has no further slashes
+            const prefix = currentPath.endsWith("/") ? currentPath : currentPath + "/";
+            if (!node.path.startsWith(prefix)) return false;
+            if (node.path === currentPath) return false;
+
+            const sub = node.path.slice(prefix.length);
+            return !sub.includes("/");
         });
 
         // Sort: Folders first, then Alphabetical