diff --git a/packages/backend/src/server/api/endpoints/admin/show-users.ts b/packages/backend/src/server/api/endpoints/admin/show-users.ts
index d28f9c71b..5471ef9b4 100644
--- a/packages/backend/src/server/api/endpoints/admin/show-users.ts
+++ b/packages/backend/src/server/api/endpoints/admin/show-users.ts
@@ -2,6 +2,7 @@ import { Inject, Injectable } from '@nestjs/common';
 import type { UsersRepository } from '@/models/index.js';
 import { Endpoint } from '@/server/api/endpoint-base.js';
 import { DI } from '@/di-symbols.js';
+import { UserEntityService } from '@/core/entities/UserEntityService.js';
 
 export const meta = {
 	tags: ['admin'],
@@ -45,6 +46,8 @@ export default class extends Endpoint<typeof meta, typeof paramDef> {
 	constructor(
 		@Inject(DI.usersRepository)
 		private usersRepository: UsersRepository,
+
+		private userEntityService: UserEntityService,
 	) {
 		super(meta, paramDef, async (ps, me) => {
 			const query = this.usersRepository.createQueryBuilder('user');
diff --git a/packages/client/src/components/MkUrlPreview.vue b/packages/client/src/components/MkUrlPreview.vue
index 9b2a78535..af27f644e 100644
--- a/packages/client/src/components/MkUrlPreview.vue
+++ b/packages/client/src/components/MkUrlPreview.vue
@@ -10,7 +10,7 @@
 	<transition :name="$store.state.animation ? 'zoom' : ''" mode="out-in">
 		<component :is="self ? 'MkA' : 'a'" v-if="!fetching" class="link" :class="{ compact }" :[attr]="self ? url.substr(local.length) : url" rel="nofollow noopener" :target="target" :title="url">
 			<div v-if="thumbnail" class="thumbnail" :style="`background-image: url('${thumbnail}')`">
-				<button v-if="!playerEnabled && player.url" class="_button" :title="i18n.ts.enablePlayer" @click.prevent="playerEnabled = true"><i class="fas fa-play-circle"></i></button>
+				<button v-if="!playerEnabled && player.url" class="_button" :title="i18n.ts.enablePlayer" @click.prevent="isMobile? playerEnabled = true : openPlayer()"><i class="fas fa-play-circle"></i></button>
 			</div>
 			<article>
 				<header>
@@ -33,9 +33,11 @@
 </template>
 
 <script lang="ts" setup>
-import { onMounted, onUnmounted } from 'vue';
+import { defineAsyncComponent, onMounted, onUnmounted } from 'vue';
 import { url as local, lang } from '@/config';
 import { i18n } from '@/i18n';
+import * as os from '@/os';
+import { deviceKind } from '@/scripts/device-kind';
 
 const props = withDefaults(defineProps<{
 	url: string;
@@ -46,6 +48,9 @@ const props = withDefaults(defineProps<{
 	compact: false,
 });
 
+const MOBILE_THRESHOLD = 500;
+const isMobile = $ref(deviceKind === 'smartphone' || window.innerWidth <= MOBILE_THRESHOLD);
+
 const self = props.url.startsWith(local);
 const attr = self ? 'to' : 'href';
 const target = self ? null : '_blank';
@@ -103,6 +108,12 @@ function adjustTweetHeight(message: any) {
 	if (height) tweetHeight = height;
 }
 
+const openPlayer = (): void => {
+	os.popup(defineAsyncComponent(() => import('@/components/MkYoutubePlayer.vue')), {
+		url: requestUrl.href,
+	});
+};
+
 (window as any).addEventListener('message', adjustTweetHeight);
 
 onUnmounted(() => {
diff --git a/packages/client/src/components/MkYoutubePlayer.vue b/packages/client/src/components/MkYoutubePlayer.vue
new file mode 100644
index 000000000..0d8eb75b8
--- /dev/null
+++ b/packages/client/src/components/MkYoutubePlayer.vue
@@ -0,0 +1,72 @@
+<template>
+<XWindow :initial-width="640" :initial-height="402" :can-resize="true" :close-button="true">
+	<template #header>
+		<i class="icon fa-brands fa-youtube" style="margin-right: 0.5em;"></i>
+		<span>{{ title ?? 'Youtube Player' }}</span>
+	</template>
+
+	<div class="poamfof">
+		<transition :name="$store.state.animation ? 'fade' : ''" mode="out-in">
+			<div v-if="player.url" class="player">
+				<iframe v-if="!fetching" :src="player.url + (player.url.match(/\?/) ? '&autoplay=1&auto_play=1' : '?autoplay=1&auto_play=1')" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen/>
+			</div>
+		</transition>
+		<MkLoading v-if="fetching"/>
+		<MkError v-else-if="!player.url" @retry="ytFetch()"/>
+	</div>
+</XWindow>
+</template>
+
+<script lang="ts" setup>
+import XWindow from '@/components/MkWindow.vue';
+import { lang } from '@/config';
+
+const props = defineProps<{
+	url: string;
+}>();
+
+const requestUrl = new URL(props.url);
+
+let fetching = $ref(true);
+let title = $ref<string | null>(null);
+let player = $ref({
+	url: null,
+	width: null,
+	height: null,
+});
+
+const requestLang = (lang ?? 'ja-JP').replace('ja-KS', 'ja-JP');
+
+const ytFetch = (): void => {
+	fetching = true;
+	fetch(`/url?url=${encodeURIComponent(requestUrl.href)}&lang=${requestLang}`).then(res => {
+		res.json().then(info => {
+			if (info.url == null) return;
+			title = info.title;
+			fetching = false;
+			player = info.player;
+		});
+	});
+};
+
+ytFetch();
+
+</script>
+
+<style lang="scss">
+.poamfof {
+	position: relative;
+	overflow: hidden;
+	height: 100%;
+
+	.player {
+		position: absolute;
+		inset: 0;
+
+		iframe {
+			width: 100%;
+			height: 100%;
+		}
+	}
+}
+</style>