diff --git a/control/frontend/src/lib/components/InodeElement.svelte b/control/frontend/src/lib/components/InodeElement.svelte
index 72bff2e..6c77515 100755
--- a/control/frontend/src/lib/components/InodeElement.svelte
+++ b/control/frontend/src/lib/components/InodeElement.svelte
@@ -11,7 +11,10 @@
 		type Inode,
 		get_file_primary_key,
 		type FileOnDisplay,
-		type FileTransferTask
+		type FileTransferTask,
+
+		is_folder
+
 	} from '$lib/ts/types';
 
 	import {
@@ -69,7 +72,7 @@
 		get_date_mapping(file_primary_key)
 	);
 
-	const is_folder = file.type === 'inode/directory';
+	const file_is_folder = $derived(is_folder(file));
 
 	function get_created_info(date_mapping: Record<string, Date> | undefined, full_string = false) {
 		if (!date_mapping) return '';
@@ -149,7 +152,7 @@
 	}
 
 	async function open() {
-		if (is_folder) {
+		if (file_is_folder) {
 			await change_file_path($current_file_path + file.name + '/');
 		} else {
 			const path_to_file = $current_file_path + file.name;
@@ -213,28 +216,28 @@
 	{#if !not_interactable}
 		<div class="h-{$current_height.file} aspect-square max-w-15 flex">
 			<Button
-				disabled={!is_folder && get_file_type(file) === null}
-				title={!is_folder && get_file_type(file) === null ? 'Dateityp nicht unterstützt' : ''}
-				className="flex rounded-l-lg rounded-r-none {is_folder
+				disabled={!file_is_folder && get_file_type(file) === null}
+				title={!file_is_folder && get_file_type(file) === null ? 'Dateityp nicht unterstützt' : ''}
+				className="flex rounded-l-lg rounded-r-none {file_is_folder
 					? 'text-stone-450'
 					: 'text-stone-800'} w-full"
 				div_class="w-full"
 				bg={get_selectable_color_classes(
-					!is_folder && get_file_type(file) !== null,
+					!file_is_folder && get_file_type(file) !== null,
 					{
 						bg: true
 					},
 					-50
 				)}
 				hover_bg={get_selectable_color_classes(
-					!is_folder,
+					!file_is_folder,
 					{
 						bg: true
 					},
 					50
 				)}
 				active_bg={get_selectable_color_classes(
-					!is_folder,
+					!file_is_folder,
 					{
 						bg: true
 					},
@@ -245,7 +248,7 @@
 					e.stopPropagation();
 				}}
 			>
-				{#if is_folder}
+				{#if file_is_folder}
 					<ArrowRight class="size-full" strokeWidth="3" />
 				{:else if $missing_colliding_displays_ids && $missing_colliding_displays_ids.missing.length !== 0}
 					<RefreshPlay className="size-full" />
@@ -274,7 +277,7 @@
 		{/if}
 		<div class="flex flex-row gap-2 min-w-0 w-full z-10">
 			<div class="aspect-square rounded-md flex justify-center items-center">
-				{#if is_folder}
+				{#if file_is_folder}
 					<Folder class="size-full p-2" />
 				{:else if $thumbnail_url || null}
 					<img
@@ -291,7 +294,7 @@
 				{/if}
 			</div>
 			<div class="content-center truncate select-none w-full" title={file.name}>
-				{file.name.includes('.') && !is_folder && get_file_type(file)
+				{file.name.includes('.') && !file_is_folder && get_file_type(file)
 					? file.name.slice(0, file.name.lastIndexOf('.'))
 					: file.name}
 			</div>
@@ -343,7 +346,7 @@
 				class="w-12 content-center text-center select-none text-xs whitespace-nowrap truncate"
 				title={file.type}
 			>
-				{is_folder ? 'Ordner' : (get_file_type(file)?.display_name ?? '?')}
+				{file_is_folder ? 'Ordner' : (get_file_type(file)?.display_name ?? '?')}
 			</div>
 			<div
 				class="h-[70%] border {get_grayed_out_border_color_strings(
diff --git a/control/frontend/src/lib/ts/file_transfer_handler.ts b/control/frontend/src/lib/ts/file_transfer_handler.ts
index d3e2281..d15de2f 100644
--- a/control/frontend/src/lib/ts/file_transfer_handler.ts
+++ b/control/frontend/src/lib/ts/file_transfer_handler.ts
@@ -12,6 +12,7 @@ import { notifications } from './stores/notification';
 import { generate_thumbnail } from './stores/thumbnails';
 import {
 	get_file_primary_key,
+	is_folder,
 	type FileLoadingData,
 	type FileOnDisplay,
 	type FileTransferTask,
@@ -109,7 +110,7 @@ export async function add_sync_recursively(
 	);
 	if (!file_data) return console.warn('Sync canceled: no file_data');
 
-	if (file_data.file.type === 'inode/directory') {
+	if (is_folder(file_data.file)) {
 		const new_path = file_data.file.path + file_data.file.name + '/';
 		const elements_in_folder = await get_folder_elements(new_path, selected_display_ids);
 		if (elements_in_folder.length === 0) {
@@ -294,7 +295,7 @@ export async function download_file(selected_file_id: string, selected_display_i
 		selected_file_id,
 		selected_display_ids
 	);
-	if (!file_data || file_data.file.type === 'inode/directory')
+	if (!file_data || is_folder(file_data.file))
 		return console.warn('Download cancelled: is folder');
 
 	try {
diff --git a/control/frontend/src/lib/ts/stores/files.ts b/control/frontend/src/lib/ts/stores/files.ts
index 18985b5..79a17c2 100755
--- a/control/frontend/src/lib/ts/stores/files.ts
+++ b/control/frontend/src/lib/ts/stores/files.ts
@@ -1,6 +1,7 @@
 import { get, writable, type Writable } from 'svelte/store';
 import {
 	get_file_primary_key,
+	is_folder,
 	type Display,
 	type FileOnDisplay,
 	type Inode,
@@ -59,7 +60,7 @@ export async function remove_file_from_display_recusively(
 
 	const inode_element = await get_file_by_id(found.file_primary_key);
 	if (!inode_element) return;
-	if (inode_element.type === 'inode/directory') {
+	if (is_folder(inode_element)) {
 		const path_inside_folder = inode_element.path + inode_element.name + `/`;
 		const primary_file_keys_in_folder = (
 			await db.files.where('path').equals(path_inside_folder).toArray()
@@ -149,7 +150,7 @@ export async function get_displays_where_path_not_exists(
 	const folders_of_current_path = await db.files
 		.where('name')
 		.equals(last_path_part)
-		.filter((inode) => inode.path === path_without_last_part && inode.type === 'inode/directory')
+		.filter((inode) => inode.path === path_without_last_part && is_folder(inode))
 		.first();
 	if (!folders_of_current_path) return [];
 	const folder_primary_key = get_file_primary_key(folders_of_current_path);
@@ -278,7 +279,7 @@ export async function update_folder_elements_recursively(
 			};
 			await db.files_on_display.put(file_on_display);
 
-			if (new_element.folder_element.type === 'inode/directory') {
+			if (is_folder(new_element.folder_element)) {
 				await update_folder_elements_recursively(
 					display,
 					file_path + new_element.folder_element.name + '/'
@@ -334,8 +335,8 @@ export async function get_folder_elements(
 
 function sort_files(files: Inode[]) {
 	files.sort((a, b) => {
-		const isDirA = a.type === 'inode/directory';
-		const isDirB = b.type === 'inode/directory';
+		const isDirA = is_folder(a);
+		const isDirB = is_folder(b);
 
 		// Ordner zuerst
 		if (isDirA && !isDirB) return -1;
diff --git a/control/frontend/src/lib/ts/types.ts b/control/frontend/src/lib/ts/types.ts
index 187a9f0..f9966e4 100755
--- a/control/frontend/src/lib/ts/types.ts
+++ b/control/frontend/src/lib/ts/types.ts
@@ -46,7 +46,7 @@ export type FileTransferTaskData =
 			type: 'sync';
 			destination_display_data: {
 				display: ShortDisplay;
-				loading_data: FileLoadingData
+				loading_data: FileLoadingData;
 			}[];
 	  };
 
@@ -135,11 +135,11 @@ export type PopupContent = {
 };
 
 export type NumberSetting = {
-	max: number,
-	min: number,
-	now: number,
-	step: number
-}
+	max: number;
+	min: number;
+	now: number;
+	step: number;
+};
 
 export type DisplayStatus = 'host_offline' | 'app_offline' | 'app_online' | null;
 
@@ -148,3 +148,7 @@ export function to_display_status(value: string): DisplayStatus {
 		? (value as DisplayStatus)
 		: null;
 }
+
+export function is_folder(inode: Inode) {
+	return inode.type === 'inode/directory';
+}
diff --git a/control/frontend/src/routes/FileView.svelte b/control/frontend/src/routes/FileView.svelte
index 7895d31..9d4dd18 100755
--- a/control/frontend/src/routes/FileView.svelte
+++ b/control/frontend/src/routes/FileView.svelte
@@ -27,7 +27,7 @@
 	import { slide } from 'svelte/transition';
 	import InodeElement from '../lib/components/InodeElement.svelte';
 	import PopUp from '$lib/components/PopUp.svelte';
-	import { get_file_primary_key, type Inode, type PopupContent } from '$lib/ts/types';
+	import { get_file_primary_key, is_folder, type Inode, type PopupContent } from '$lib/ts/types';
 	import TextInput from '$lib/components/TextInput.svelte';
 	import {
 		first_letter_is_valid,
@@ -59,7 +59,9 @@
 	$effect(() => {
 		const s = $selected_file_ids;
 		one_file_selected = liveQuery(async () => {
-			return s.length === 1 && (await get_file_by_id(s[0]))?.type !== 'inode/directory';
+			const inode = await get_file_by_id(s[0]);
+			if (!inode) return false;
+			return s.length === 1 && is_folder(inode);
 		});
 	});
 
@@ -110,14 +112,14 @@
 	const show_edit_file_popup = async () => {
 		const file = await get_file_by_id($selected_file_ids[0]);
 		if (!file) return;
-		const is_folder = file.type === 'inode/directory';
-		const extension = is_folder ? '' : '.' + file.name.split('.').at(-1) || '';
+		const file_is_folder = is_folder(file);
+		const extension = file_is_folder ? '' : '.' + file.name.split('.').at(-1) || '';
 		current_name = file.name.slice(0, file.name.length - extension.length);
 		current_valid = true;
 		popup_content = {
 			open: true,
 			snippet: edit_file_name_popup,
-			title: `${is_folder ? 'Ordner' : 'Datei'} umbenennen`,
+			title: `${file_is_folder ? 'Ordner' : 'Datei'} umbenennen`,
 			title_icon: FolderPlus,
 			snippet_arg: extension,
 		};