diff --git a/packages/embed/src/boot.ts b/packages/embed/src/boot.ts
index f1a12336cc..f9f409ee1a 100644
--- a/packages/embed/src/boot.ts
+++ b/packages/embed/src/boot.ts
@@ -10,7 +10,6 @@ import '@/style.scss';
 import { createApp, defineAsyncComponent } from 'vue';
 import { setIframeId, postMessageToParentWindow } from '@/scripts/post-message.js';
 import { parseEmbedParams } from '@/embed-page.js';
-import { createEmbedRouter } from '@/router.js';
 
 const params = new URLSearchParams(location.search);
 const embedParams = parseEmbedParams(params);
diff --git a/packages/embed/src/embed-page.ts b/packages/embed/src/embed-page.ts
new file mode 100644
index 0000000000..4a026f705d
--- /dev/null
+++ b/packages/embed/src/embed-page.ts
@@ -0,0 +1,88 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+//#region Embed関連の定義
+
+/** 埋め込みの対象となるエンティティ（/embed/xxx の xxx の部分と対応させる） */
+const embeddableEntities = [
+	'notes',
+	'user-timeline',
+	'clips',
+	'tags',
+] as const;
+
+/** 埋め込みの対象となるエンティティ */
+export type EmbeddableEntity = typeof embeddableEntities[number];
+
+/** 内部でスクロールがあるページ */
+export const embedRouteWithScrollbar: EmbeddableEntity[] = [
+	'clips',
+	'tags',
+	'user-timeline',
+];
+
+/** 埋め込みコードのパラメータ */
+export type EmbedParams = {
+	maxHeight?: number;
+	colorMode?: 'light' | 'dark';
+	rounded?: boolean;
+	border?: boolean;
+	autoload?: boolean;
+	header?: boolean;
+};
+
+/** 正規化されたパラメータ */
+export type ParsedEmbedParams = Required<Omit<EmbedParams, 'maxHeight' | 'colorMode'>> & Pick<EmbedParams, 'maxHeight' | 'colorMode'>;
+
+/** パラメータのデフォルトの値 */
+export const defaultEmbedParams = {
+	maxHeight: undefined,
+	colorMode: undefined,
+	rounded: true,
+	border: true,
+	autoload: false,
+	header: true,
+} as const satisfies EmbedParams;
+
+//#endregion
+
+/**
+ * パラメータを正規化する（埋め込みページ初期化用）
+ * @param searchParams URLSearchParamsもしくはクエリ文字列
+ * @returns 正規化されたパラメータ
+ */
+export function parseEmbedParams(searchParams: URLSearchParams | string): ParsedEmbedParams {
+	let _searchParams: URLSearchParams;
+	if (typeof searchParams === 'string') {
+		_searchParams = new URLSearchParams(searchParams);
+	} else if (searchParams instanceof URLSearchParams) {
+		_searchParams = searchParams;
+	} else {
+		throw new Error('searchParams must be URLSearchParams or string');
+	}
+
+	const params: EmbedParams = {};
+	for (const key in defaultEmbedParams) {
+		const value = _searchParams.get(key);
+		if (value != null) {
+			if (value === 'true') {
+				params[key] = true;
+			} else if (value === 'false') {
+				params[key] = false;
+			} else if (!isNaN(Number(value))) {
+				params[key] = Number(value);
+			} else if (key === 'colorMode' && ['light', 'dark'].includes(value)) {
+				params[key] = value as 'light' | 'dark';
+			} else {
+				params[key] = value;
+			}
+		}
+	}
+
+	return {
+		...defaultEmbedParams,
+		...params,
+	};
+}
diff --git a/packages/frontend/src/config.ts b/packages/frontend/src/config.ts
index cdc7e88ba3..277dfc12aa 100644
--- a/packages/frontend/src/config.ts
+++ b/packages/frontend/src/config.ts
@@ -4,7 +4,6 @@
  */
 
 import { miLocalStorage } from '@/local-storage.js';
-import { isEmbedPage } from '@/scripts/embed-page.js';
 
 const address = new URL(document.querySelector<HTMLMetaElement>('meta[property="instance_url"]')?.content || location.href);
 const siteName = document.querySelector<HTMLMetaElement>('meta[property="og:site_name"]')?.content;
@@ -22,9 +21,6 @@ export const version = _VERSION_;
 export const instanceName = siteName === 'Misskey' || siteName == null ? host : siteName;
 export const ui = miLocalStorage.getItem('ui');
 export const debug = miLocalStorage.getItem('debug') === 'true';
-// config.tsでインポートしているファイルと、その内部で使用される関数では使用できない。
-// それらでembedPageの判定をしたい場合は関数を直接呼び出すこと
-export const embedPage = isEmbedPage();
 
 export function updateLocale(newLocale): void {
 	locale = newLocale;
diff --git a/packages/frontend/src/local-storage.ts b/packages/frontend/src/local-storage.ts
index 8803801f47..59ca455362 100644
--- a/packages/frontend/src/local-storage.ts
+++ b/packages/frontend/src/local-storage.ts
@@ -2,7 +2,6 @@
  * SPDX-FileCopyrightText: syuilo and misskey-project
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-import { isEmbedPage } from '@/scripts/embed-page.js';
 
 export type Keys =
 	'v' |
@@ -45,25 +44,18 @@ export type Keys =
 // セッション毎に廃棄されるLocalStorage代替（embedなどで使用）
 const safeSessionStorage = new Map<Keys, string>();
 
-const embedPage = isEmbedPage();
-
 export const miLocalStorage = {
 	getItem: (key: Keys): string | null => {
-		if (embedPage) {
-			return safeSessionStorage.get(key) ?? null;
-		}
 		return window.localStorage.getItem(key);
 	},
 	setItem: (key: Keys, value: string): void => {
-		if (embedPage) {
-			safeSessionStorage.set(key, value);
+		if (false) {
 		} else {
 			window.localStorage.setItem(key, value);
 		}
 	},
 	removeItem: (key: Keys): void => {
-		if (embedPage) {
-			safeSessionStorage.delete(key);
+		if (false) {
 		} else {
 			window.localStorage.removeItem(key);
 		}
@@ -79,26 +71,3 @@ export const miLocalStorage = {
 		miLocalStorage.setItem(key, JSON.stringify(value));
 	},
 };
-
-if (embedPage) {
-	/**
-	 * EmbedページではlocalStorageを使用できないようにしているが、
-	 * 動作に必要な値はsafeSessionStorageに移動する
-	 */
-	const keysToDuplicate: Keys[] = [
-		'v',
-		'instance',
-		'instanceCachedAt',
-		'lang',
-		'locale',
-		'localeVersion',
-	];
-
-	keysToDuplicate.forEach(key => {
-		const value = window.localStorage.getItem(key);
-		if (value && !miLocalStorage.getItem(key)) {
-			miLocalStorage.setItem(key, value);
-		}
-	});
-	if (_DEV_) console.warn('Using safeSessionStorage as localStorage alternative');
-}
diff --git a/packages/frontend/src/scripts/embed-page.ts b/packages/frontend/src/scripts/embed-page.ts
index ffbb07cd16..84ca2ed381 100644
--- a/packages/frontend/src/scripts/embed-page.ts
+++ b/packages/frontend/src/scripts/embed-page.ts
@@ -5,16 +5,6 @@
 
 //#region Embed関連の定義
 
-let _isEmbedPage: boolean | null = null;
-
-/** 埋め込みページかどうか */
-export function isEmbedPage() {
-	if (_isEmbedPage === null) {
-		_isEmbedPage = location.pathname.startsWith('/embed/');
-	}
-	return _isEmbedPage;
-}
-
 /** 埋め込みの対象となるエンティティ（/embed/xxx の xxx の部分と対応させる） */
 const embeddableEntities = [
 	'notes',
@@ -30,7 +20,7 @@ export type EmbeddableEntity = typeof embeddableEntities[number];
 export const embedRouteWithScrollbar: EmbeddableEntity[] = [
 	'clips',
 	'tags',
-	'user-timeline'
+	'user-timeline',
 ];
 
 /** 埋め込みコードのパラメータ */
@@ -57,42 +47,3 @@ export const defaultEmbedParams = {
 } as const satisfies EmbedParams;
 
 //#endregion
-
-/**
- * パラメータを正規化する（埋め込みページ初期化用）
- * @param searchParams URLSearchParamsもしくはクエリ文字列
- * @returns 正規化されたパラメータ
- */
-export function parseEmbedParams(searchParams: URLSearchParams | string): ParsedEmbedParams {
-	let _searchParams: URLSearchParams;
-	if (typeof searchParams === 'string') {
-		_searchParams = new URLSearchParams(searchParams);
-	} else if (searchParams instanceof URLSearchParams) {
-		_searchParams = searchParams;
-	} else {
-		throw new Error('searchParams must be URLSearchParams or string');
-	}
-
-	const params: EmbedParams = {};
-	for (const key in defaultEmbedParams) {
-		const value = _searchParams.get(key);
-		if (value != null) {
-			if (value === 'true') {
-				params[key] = true;
-			} else if (value === 'false') {
-				params[key] = false;
-			} else if (!isNaN(Number(value))) {
-				params[key] = Number(value);
-			} else if (key === 'colorMode' && ['light', 'dark'].includes(value)) {
-				params[key] = value as 'light' | 'dark';
-			} else {
-				params[key] = value;
-			}
-		}
-	}
-
-	return {
-		...defaultEmbedParams,
-		...params,
-	};
-}