diff --git a/CHANGELOG.md b/CHANGELOG.md
index 03b1bb4e2..972958963 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -103,6 +103,7 @@ Meilisearchの設定に`index`が必要になりました。値はMisskeyサー
   * 画像が全て隠れた状態で表示されるようになります
 - 閲覧注意設定された画像は表示した状態でもそれが閲覧注意だと分かる表示をするように
 - モデレーターはノートに添付された画像上から直接NSFW設定できるように
+- 1枚だけのメディアリストの画像のアスペクト比を画像に応じて縦長にするように
 - プロフィール設定「追加情報」の項目の削除と並び替えができるように
 - 新しい実績を追加
 - AiScriptを0.13.2に更新
diff --git a/packages/frontend/package.json b/packages/frontend/package.json
index 7e6c1442b..2f754f8aa 100644
--- a/packages/frontend/package.json
+++ b/packages/frontend/package.json
@@ -25,9 +25,9 @@
 		"@vue-macros/reactivity-transform": "0.3.7",
 		"@vue/compiler-sfc": "3.3.2",
 		"autosize": "6.0.1",
-		"blurhash": "2.0.5",
 		"broadcast-channel": "4.20.2",
 		"browser-image-resizer": "github:misskey-dev/browser-image-resizer#v2.2.1-misskey.3",
+		"buraha": "github:misskey-dev/buraha",
 		"canvas-confetti": "1.6.0",
 		"chart.js": "4.3.0",
 		"chartjs-adapter-date-fns": "3.0.0",
diff --git a/packages/frontend/src/components/MkGalleryPostPreview.vue b/packages/frontend/src/components/MkGalleryPostPreview.vue
index 4f8f7b945..fccc33dcc 100644
--- a/packages/frontend/src/components/MkGalleryPostPreview.vue
+++ b/packages/frontend/src/components/MkGalleryPostPreview.vue
@@ -5,12 +5,9 @@
 			<ImgWithBlurhash
 				class="img layered"
 				:transition="safe ? null : {
-					enterActiveClass: $style.transition_toggle_enterActive,
+					duration: 500,
 					leaveActiveClass: $style.transition_toggle_leaveActive,
-					enterFromClass: $style.transition_toggle_enterFrom,
 					leaveToClass: $style.transition_toggle_leaveTo,
-					enterToClass: $style.transition_toggle_enterTo,
-					leaveFromClass: $style.transition_toggle_leaveFrom,
 				}"
 				:src="post.files[0].thumbnailUrl"
 				:hash="post.files[0].blurhash"
@@ -53,24 +50,16 @@ function leaveHover(): void {
 </script>
 
 <style lang="scss" module>
-.transition_toggle_enterActive,
 .transition_toggle_leaveActive {
-	transition: opacity 0.5s;
+	transition: opacity .5s;
 	position: absolute;
 	top: 0;
 	left: 0;
 }
 
-.transition_toggle_enterFrom,
 .transition_toggle_leaveTo {
 	opacity: 0;
 }
-
-.transition_toggle_enterTo,
-.transition_toggle_leaveFrom {
-	transition: none;
-	opacity: 1;
-}
 </style>
 
 <style lang="scss" scoped>
diff --git a/packages/frontend/src/components/MkImgWithBlurhash.vue b/packages/frontend/src/components/MkImgWithBlurhash.vue
index 6406a3506..de14d9ea2 100644
--- a/packages/frontend/src/components/MkImgWithBlurhash.vue
+++ b/packages/frontend/src/components/MkImgWithBlurhash.vue
@@ -1,30 +1,56 @@
 <template>
-<div :class="[$style.root, { [$style.cover]: cover }]" :title="title ?? ''">
-	<img v-if="!loaded && src && !forceBlurhash" :class="$style.loader" :src="src" @load="onLoad"/>
-	<Transition
-		mode="in-out"
-		:enter-active-class="defaultStore.state.animation && (props.transition?.enterActiveClass ?? $style['transition_toggle_enterActive']) || undefined"
-		:leave-active-class="defaultStore.state.animation && (props.transition?.leaveActiveClass ?? $style['transition_toggle_leaveActive']) || undefined"
+<div ref="root" :class="[$style.root, { [$style.cover]: cover }]" :title="title ?? ''">
+	<TransitionGroup
+		:duration="defaultStore.state.animation && props.transition?.duration || undefined"
+		:enter-active-class="defaultStore.state.animation && props.transition?.enterActiveClass || undefined"
+		:leave-active-class="defaultStore.state.animation && (props.transition?.leaveActiveClass ?? $style['transition_leaveActive']) || undefined"
 		:enter-from-class="defaultStore.state.animation && props.transition?.enterFromClass || undefined"
 		:leave-to-class="defaultStore.state.animation && props.transition?.leaveToClass || undefined"
-		:enter-to-class="defaultStore.state.animation && (props.transition?.enterToClass ?? $style['transition_toggle_enterTo']) || undefined"
-		:leave-from-class="defaultStore.state.animation && (props.transition?.leaveFromClass ?? $style['transition_toggle_leaveFrom']) || undefined"
+		:enter-to-class="defaultStore.state.animation && props.transition?.enterToClass || undefined"
+		:leave-from-class="defaultStore.state.animation && props.transition?.leaveFromClass || undefined"
 	>
-		<canvas v-if="!loaded || forceBlurhash" ref="canvas" :class="$style.canvas" :width="width" :height="height" :title="title ?? undefined"/>
-		<img v-else :class="$style.img" :src="src ?? undefined" :title="title ?? undefined" :alt="alt ?? undefined"/>
-	</Transition>
+		<canvas v-show="hide" key="canvas" ref="canvas" :class="$style.canvas" :width="canvasWidth" :height="canvasHeight" :title="title ?? undefined"/>
+		<img v-show="!hide" key="img" ref="img" :height="imgHeight" :width="imgWidth" :class="$style.img" :src="src ?? undefined" :title="title ?? undefined" :alt="alt ?? undefined" loading="eager" decoding="async"/>
+	</TransitionGroup>
 </div>
 </template>
 
-<script lang="ts" setup>
-import { onMounted, shallowRef, useCssModule, watch } from 'vue';
-import { decode } from 'blurhash';
-import { defaultStore } from '@/store';
+<script lang="ts">
+import DrawBlurhash from '@/workers/draw-blurhash?worker';
+import TestWebGL2 from '@/workers/test-webgl2?worker';
+import { WorkerMultiDispatch } from '@/scripts/worker-multi-dispatch';
+import { $ref } from 'vue/macros';
+import { extractAvgColorFromBlurhash } from '@/scripts/extract-avg-color-from-blurhash';
 
+const workerPromise = new Promise<WorkerMultiDispatch | null>(resolve => {
+	const testWorker = new TestWebGL2();
+	testWorker.addEventListener('message', event => {
+		if (event.data.result) {
+			const workers = new WorkerMultiDispatch(
+				() => new DrawBlurhash(),
+				Math.min(navigator.hardwareConcurrency - 1, 4),
+			);
+			resolve(workers);
+			if (_DEV_) console.log('WebGL2 in worker is supported!');
+		} else {
+			resolve(null);
+			if (_DEV_) console.log('WebGL2 in worker is not supported...');
+		}
+		testWorker.terminate();
+	});
+});
+</script>
+
+<script lang="ts" setup>
+import { computed, nextTick, onMounted, onUnmounted, shallowRef, useCssModule, watch } from 'vue';
+import { v4 as uuid } from 'uuid';
+import { render } from 'buraha';
+import { defaultStore } from '@/store';
 const $style = useCssModule();
 
 const props = withDefaults(defineProps<{
 	transition?: {
+		duration?: number | { enter: number; leave: number; };
 		enterActiveClass?: string;
 		leaveActiveClass?: string;
 		enterFromClass?: string;
@@ -51,67 +77,141 @@ const props = withDefaults(defineProps<{
 	forceBlurhash: false,
 });
 
+const viewId = uuid();
 const canvas = shallowRef<HTMLCanvasElement>();
+const root = shallowRef<HTMLDivElement>();
+const img = shallowRef<HTMLImageElement>();
 let loaded = $ref(false);
-let width = $ref(props.width);
-let height = $ref(props.height);
+let canvasWidth = $ref(64);
+let canvasHeight = $ref(64);
+let imgWidth = $ref(props.width);
+let imgHeight = $ref(props.height);
+let bitmapTmp = $ref<CanvasImageSource | undefined>();
+const hide = computed(() => !loaded || props.forceBlurhash);
 
-function onLoad() {
-	loaded = true;
+function waitForDecode() {
+	if (props.src != null && props.src !== '') {
+		nextTick()
+			.then(() => img.value?.decode())
+			.then(() => {
+				loaded = true;
+			}, error => {
+				console.error('Error occured during decoding image', img.value, error);
+				throw Error(error);
+			});
+	} else {
+		loaded = false;
+	}
 }
 
-watch([() => props.width, () => props.height], () => {
+watch([() => props.width, () => props.height, root], () => {
 	const ratio = props.width / props.height;
 	if (ratio > 1) {
-		width = Math.round(64 * ratio);
-		height = 64;
+		canvasWidth = Math.round(64 * ratio);
+		canvasHeight = 64;
 	} else {
-		width = 64;
-		height = Math.round(64 / ratio);
+		canvasWidth = 64;
+		canvasHeight = Math.round(64 / ratio);
 	}
+
+	const clientWidth = root.value?.clientWidth ?? 300;
+	imgWidth = clientWidth;
+	imgHeight = Math.round(clientWidth / ratio);
 }, {
 	immediate: true,
 });
 
-function draw() {
-	if (props.hash == null || !canvas.value) return;
-	const pixels = decode(props.hash, width, height);
+function drawImage(bitmap: CanvasImageSource) {
+	// canvasがない（mountedされていない）場合はTmpに保存しておく
+	if (!canvas.value) {
+		bitmapTmp = bitmap;
+		return;
+	}
+
+	// canvasがあれば描画する
+	bitmapTmp = undefined;
 	const ctx = canvas.value.getContext('2d');
-	const imageData = ctx!.createImageData(width, height);
-	imageData.data.set(pixels);
-	ctx!.putImageData(imageData, 0, 0);
+	if (!ctx) return;
+	ctx.drawImage(bitmap, 0, 0, canvasWidth, canvasHeight);
 }
 
-watch([() => props.hash, canvas], () => {
+async function draw() {
+	if (!canvas.value || props.hash == null) return;
+
+	const ctx = canvas.value.getContext('2d');
+	if (!ctx) return;
+
+	// avgColorでお茶をにごす
+	ctx.beginPath();
+	ctx.fillStyle = extractAvgColorFromBlurhash(props.hash) ?? '#888';
+	ctx.fillRect(0, 0, canvasWidth, canvasHeight);
+
+	const workers = await workerPromise;
+	if (workers) {
+		workers.postMessage(
+			{
+				id: viewId,
+				hash: props.hash,
+				width: canvasWidth,
+				height: canvasHeight,
+			},
+			undefined,
+		);
+	} else {
+		try {
+			const work = document.createElement('canvas');
+			work.width = canvasWidth;
+			work.height = canvasHeight;
+			render(props.hash, work);
+			ctx.drawImage(work, 0, 0, canvasWidth, canvasHeight);
+		} catch (error) {
+			console.error('Error occured during drawing blurhash', error);
+		}
+	}
+}
+
+function workerOnMessage(event: MessageEvent) {
+	if (event.data.id !== viewId) return;
+	drawImage(event.data.bitmap as ImageBitmap);
+}
+
+workerPromise.then(worker => {
+	if (worker) {
+		worker.addListener(workerOnMessage);
+	}
+
+	draw();
+});
+
+watch(() => props.src, () => {
+	waitForDecode();
+});
+
+watch(() => props.hash, () => {
 	draw();
 });
 
 onMounted(() => {
-	draw();
+	// drawImageがmountedより先に呼ばれている場合はここで描画する
+	if (bitmapTmp) {
+		drawImage(bitmapTmp);
+	}
+	waitForDecode();
+});
+
+onUnmounted(() => {
+	workerPromise.then(worker => {
+		worker?.removeListener(workerOnMessage);
+	});
 });
 </script>
 
 <style lang="scss" module>
-.transition_toggle_enterActive,
-.transition_toggle_leaveActive {
+.transition_leaveActive {
 	position: absolute;
 	top: 0;
 	left: 0;
 }
-
-.transition_toggle_enterTo,
-.transition_toggle_leaveFrom {
-	opacity: 0;
-}
-
-.loader {
-	position: absolute;
-	top: 0;
-	left: 0;
-	width: 0;
-	height: 0;
-}
-
 .root {
 	position: relative;
 	width: 100%;
diff --git a/packages/frontend/src/components/MkMediaImage.vue b/packages/frontend/src/components/MkMediaImage.vue
index 42dc9e79f..b235dd8bd 100644
--- a/packages/frontend/src/components/MkMediaImage.vue
+++ b/packages/frontend/src/components/MkMediaImage.vue
@@ -1,29 +1,40 @@
 <template>
-<div v-if="hide" :class="$style.hidden" @click="hide = false">
-	<ImgWithBlurhash style="filter: brightness(0.5);" :hash="image.blurhash" :title="image.comment" :alt="image.comment" :width="image.properties.width" :height="image.properties.height" :force-blurhash="defaultStore.state.enableDataSaverMode"/>
-	<div :class="$style.hiddenText">
-		<div :class="$style.hiddenTextWrapper">
-			<b v-if="image.isSensitive" style="display: block;"><i class="ti ti-alert-triangle"></i> {{ i18n.ts.sensitive }}{{ defaultStore.state.enableDataSaverMode ? ` (${i18n.ts.image}${image.size ? ' ' + bytes(image.size) : ''})` : '' }}</b>
-			<b v-else style="display: block;"><i class="ti ti-photo"></i> {{ defaultStore.state.enableDataSaverMode && image.size ? bytes(image.size) : i18n.ts.image }}</b>
-			<span style="display: block;">{{ i18n.ts.clickToShow }}</span>
-		</div>
-	</div>
-</div>
-<div v-else :class="$style.visible" :style="darkMode ? '--c: rgb(255 255 255 / 2%);' : '--c: rgb(0 0 0 / 2%);'">
+<div :class="hide ? $style.hidden : $style.visible" :style="darkMode ? '--c: rgb(255 255 255 / 2%);' : '--c: rgb(0 0 0 / 2%);'" @click="onclick">
 	<a
 		:class="$style.imageContainer"
 		:href="image.url"
 		:title="image.name"
 	>
-		<ImgWithBlurhash :hash="image.blurhash" :src="url" :alt="image.comment || image.name" :title="image.comment || image.name" :width="image.properties.width" :height="image.properties.height" :cover="false"/>
+		<ImgWithBlurhash
+			:hash="image.blurhash"
+			:src="(defaultStore.state.enableDataSaverMode && hide) ? null : url"
+			:force-blurhash="hide"
+			:cover="hide"
+			:alt="image.comment || image.name"
+			:title="image.comment || image.name"
+			:width="image.properties.width"
+			:height="image.properties.height"
+			:style="hide ? 'filter: brightness(0.5);' : null"
+		/>
 	</a>
-	<div :class="$style.indicators">
-		<div v-if="['image/gif', 'image/apng'].includes(image.type)" :class="$style.indicator">GIF</div>
-		<div v-if="image.comment" :class="$style.indicator">ALT</div>
-		<div v-if="image.isSensitive" :class="$style.indicator" style="color: var(--warn);">NSFW</div>
-	</div>
-	<button v-tooltip="i18n.ts.hide" :class="$style.hide" class="_button" @click="hide = true"><i class="ti ti-eye-off"></i></button>
-	<button :class="$style.menu" class="_button" @click.stop="showMenu"><i class="ti ti-dots"></i></button>
+	<template v-if="hide">
+		<div :class="$style.hiddenText">
+			<div :class="$style.hiddenTextWrapper">
+				<b v-if="image.isSensitive" style="display: block;"><i class="ti ti-alert-triangle"></i> {{ i18n.ts.sensitive }}{{ defaultStore.state.enableDataSaverMode ? ` (${i18n.ts.image}${image.size ? ' ' + bytes(image.size) : ''})` : '' }}</b>
+				<b v-else style="display: block;"><i class="ti ti-photo"></i> {{ defaultStore.state.enableDataSaverMode && image.size ? bytes(image.size) : i18n.ts.image }}</b>
+				<span style="display: block;">{{ i18n.ts.clickToShow }}</span>
+			</div>
+		</div>
+	</template>
+	<template v-else>
+		<div :class="$style.indicators">
+			<div v-if="['image/gif', 'image/apng'].includes(image.type)" :class="$style.indicator">GIF</div>
+			<div v-if="image.comment" :class="$style.indicator">ALT</div>
+			<div v-if="image.isSensitive" :class="$style.indicator" style="color: var(--warn);">NSFW</div>
+		</div>
+		<button v-tooltip="i18n.ts.hide" :class="$style.hide" class="_button" @click.stop.prevent="hide = true"><i class="ti ti-eye-off"></i></button>
+		<button :class="$style.menu" class="_button" @click.stop="showMenu"><i class="ti ti-dots"></i></button>
+	</template>
 </div>
 </template>
 
@@ -53,6 +64,12 @@ const url = $computed(() => (props.raw || defaultStore.state.loadRawImages)
 		: props.image.thumbnailUrl,
 );
 
+function onclick() {
+	if (hide) {
+		hide = false;
+	}
+}
+
 // Plugin:register_note_view_interruptor を使って書き換えられる可能性があるためwatchする
 watch(() => props.image, () => {
 	hide = (defaultStore.state.nsfw === 'force' || defaultStore.state.enableDataSaverMode) ? true : (props.image.isSensitive && defaultStore.state.nsfw !== 'ignore');
diff --git a/packages/frontend/src/components/MkMediaList.vue b/packages/frontend/src/components/MkMediaList.vue
index e456ff3ee..0f41ef248 100644
--- a/packages/frontend/src/components/MkMediaList.vue
+++ b/packages/frontend/src/components/MkMediaList.vue
@@ -7,6 +7,7 @@
 			:class="[
 				$style.medias,
 				count <= 4 ? $style['n' + count] : $style.nMany,
+				$style[`n1${defaultStore.reactiveState.mediaListWithOneImageAppearance.value}`]
 			]"
 		>
 			<template v-for="media in mediaList.filter(media => previewable(media))">
@@ -19,7 +20,7 @@
 </template>
 
 <script lang="ts" setup>
-import { onMounted, ref, useCssModule, watch } from 'vue';
+import { onMounted, ref, useCssModule, watch, shallowRef } from 'vue';
 import * as misskey from 'misskey-js';
 import PhotoSwipeLightbox from 'photoswipe/lightbox';
 import PhotoSwipe from 'photoswipe';
@@ -38,11 +39,42 @@ const props = defineProps<{
 
 const $style = useCssModule();
 
-const gallery = ref<HTMLDivElement>();
+const gallery = shallowRef<HTMLDivElement>();
 const pswpZIndex = os.claimZIndex('middle');
 document.documentElement.style.setProperty('--mk-pswp-root-z-index', pswpZIndex.toString());
 const count = $computed(() => props.mediaList.filter(media => previewable(media)).length);
 
+function calcAspectRatio() {
+	if (!gallery.value) return;
+
+	let img = props.mediaList[0];
+
+	if (props.mediaList.length !== 1 || !(img.properties.width && img.properties.height)) {
+		gallery.value.style.aspectRatio = '';
+		return;
+	}
+
+	// アスペクト比上限設定では、横長の場合は高さを縮小させる
+	const ratioMax = (ratio: number) => `${Math.max(ratio, img.properties.width / img.properties.height).toString()} / 1`;
+
+	switch (defaultStore.state.mediaListWithOneImageAppearance) {
+		case '16_9':
+			gallery.value.style.aspectRatio = ratioMax(16 / 9);
+			break;
+		case '1_1':
+			gallery.value.style.aspectRatio = ratioMax(1);
+			break;
+		case '2_3':
+			gallery.value.style.aspectRatio = ratioMax(2 / 3);
+			break;
+		default:
+			gallery.value.style.aspectRatio = '';
+			break;
+	}
+}
+
+watch([defaultStore.reactiveState.mediaListWithOneImageAppearance, gallery], () => calcAspectRatio());
+
 onMounted(() => {
 	const lightbox = new PhotoSwipeLightbox({
 		dataSource: props.mediaList
@@ -162,12 +194,37 @@ const previewable = (file: misskey.entities.DriveFile): boolean => {
 	display: grid;
 	grid-gap: 8px;
 
-	// for webkit
 	height: 100%;
+	width: 100%;
 
 	&.n1 {
-		aspect-ratio: 16/9;
 		grid-template-rows: 1fr;
+
+		// default (expand)
+		min-height: 64px;
+		max-height: clamp(
+			64px,
+			50cqh,
+			min(360px, 50vh)
+		);
+
+		&.n116_9 {
+			min-height: none;
+			max-height: none;
+			aspect-ratio: 16 / 9; // fallback
+		}
+
+		&.n11_1{
+			min-height: none;
+			max-height: none;
+			aspect-ratio: 1 / 1; // fallback
+		}
+
+		&.n12_3 {
+			min-height: none;
+			max-height: none;
+			aspect-ratio: 2 / 3; // fallback
+		}
 	}
 
 	&.n2 {
diff --git a/packages/frontend/src/components/global/MkAvatar.vue b/packages/frontend/src/components/global/MkAvatar.vue
index 42abdcbdc..df26ca317 100644
--- a/packages/frontend/src/components/global/MkAvatar.vue
+++ b/packages/frontend/src/components/global/MkAvatar.vue
@@ -1,6 +1,6 @@
 <template>
 <component :is="link ? MkA : 'span'" v-user-preview="preview ? user.id : undefined" v-bind="bound" class="_noSelect" :class="[$style.root, { [$style.animation]: animation, [$style.cat]: user.isCat, [$style.square]: squareAvatars }]" :style="{ color }" :title="acct(user)" @click="onClick">
-	<img :class="$style.inner" :src="url" decoding="async"/>
+	<MkImgWithBlurhash :class="$style.inner" :src="url" :hash="user?.avatarBlurhash" :cover="true"/>
 	<MkUserOnlineIndicator v-if="indicator" :class="$style.indicator" :user="user"/>
 	<div v-if="user.isCat" :class="[$style.ears]">
 		<div :class="$style.earLeft">
@@ -30,6 +30,7 @@ import { extractAvgColorFromBlurhash } from '@/scripts/extract-avg-color-from-bl
 import { acct, userPage } from '@/filters/user';
 import MkUserOnlineIndicator from '@/components/MkUserOnlineIndicator.vue';
 import { defaultStore } from '@/store';
+import MkImgWithBlurhash from '../MkImgWithBlurhash.vue';
 
 const animation = $ref(defaultStore.state.animation);
 const squareAvatars = $ref(defaultStore.state.squareAvatars);
diff --git a/packages/frontend/src/pages/settings/general.vue b/packages/frontend/src/pages/settings/general.vue
index 0dfc84704..9d06d35e6 100644
--- a/packages/frontend/src/pages/settings/general.vue
+++ b/packages/frontend/src/pages/settings/general.vue
@@ -56,7 +56,7 @@
 				<option value="ignore">{{ i18n.ts._nsfw.ignore }}</option>
 				<option value="force">{{ i18n.ts._nsfw.force }}</option>
 			</MkSelect>
-		<!--
+
 			<MkRadios v-model="mediaListWithOneImageAppearance">
 				<template #label>{{ i18n.ts.mediaListWithOneImageAppearance }}</template>
 				<option value="expand">{{ i18n.ts.default }}</option>
@@ -64,7 +64,6 @@
 				<option value="1_1">{{ i18n.t('limitTo', { x: '1:1' }) }}</option>
 				<option value="2_3">{{ i18n.t('limitTo', { x: '2:3' }) }}</option>
 			</MkRadios>
-		-->
 		</div>
 	</FormSection>
 
diff --git a/packages/frontend/src/scripts/worker-multi-dispatch.ts b/packages/frontend/src/scripts/worker-multi-dispatch.ts
new file mode 100644
index 000000000..1847a8ccf
--- /dev/null
+++ b/packages/frontend/src/scripts/worker-multi-dispatch.ts
@@ -0,0 +1,75 @@
+function defaultUseWorkerNumber(prev: number, totalWorkers: number) {
+    return prev + 1;
+}
+
+export class WorkerMultiDispatch<POST = any, RETURN = any> {
+    private symbol = Symbol('WorkerMultiDispatch');
+    private workers: Worker[] = [];
+    private terminated = false;
+    private prevWorkerNumber = 0;
+    private getUseWorkerNumber = defaultUseWorkerNumber;
+    private finalizationRegistry: FinalizationRegistry<symbol>;
+
+    constructor(workerConstructor: () => Worker, concurrency: number, getUseWorkerNumber = defaultUseWorkerNumber) {
+        this.getUseWorkerNumber = getUseWorkerNumber;
+        for (let i = 0; i < concurrency; i++) {
+            this.workers.push(workerConstructor());
+        }
+
+        this.finalizationRegistry = new FinalizationRegistry(() => {
+            this.terminate();
+        });
+        this.finalizationRegistry.register(this, this.symbol);
+
+        if (_DEV_) console.log('WorkerMultiDispatch: Created', this);
+    }
+
+    public postMessage(message: POST, options?: Transferable[] | StructuredSerializeOptions, useWorkerNumber: typeof defaultUseWorkerNumber = this.getUseWorkerNumber) {
+        let workerNumber = useWorkerNumber(this.prevWorkerNumber, this.workers.length);
+        workerNumber = Math.abs(Math.round(workerNumber)) % this.workers.length;
+        if (_DEV_) console.log('WorkerMultiDispatch: Posting message to worker', workerNumber, useWorkerNumber);
+        this.prevWorkerNumber = workerNumber;
+
+        // 不毛だがunionをoverloadに突っ込めない
+        // https://stackoverflow.com/questions/66507585/overload-signatures-union-types-and-no-overload-matches-this-call-error
+        // https://github.com/microsoft/TypeScript/issues/14107
+        if (Array.isArray(options)) {
+            this.workers[workerNumber].postMessage(message, options);
+        } else {
+            this.workers[workerNumber].postMessage(message, options);
+        }
+        return workerNumber;
+    }
+
+    public addListener(callback: (this: Worker, ev: MessageEvent<RETURN>) => any, options?: boolean | AddEventListenerOptions) {
+        this.workers.forEach(worker => {
+            worker.addEventListener('message', callback, options);
+        });
+    }
+
+    public removeListener(callback: (this: Worker, ev: MessageEvent<RETURN>) => any, options?: boolean | AddEventListenerOptions) {
+        this.workers.forEach(worker => {
+            worker.removeEventListener('message', callback, options);
+        });
+    }
+
+    public terminate() {
+        this.terminated = true;
+        if (_DEV_) console.log('WorkerMultiDispatch: Terminating', this);
+        this.workers.forEach(worker => {
+            worker.terminate();
+        });
+        this.workers = [];
+        this.finalizationRegistry.unregister(this);
+    }
+
+    public isTerminated() {
+        return this.terminated;
+    }
+    public getWorkers() {
+        return this.workers;
+    }
+    public getSymbol() {
+        return this.symbol;
+    }
+}
diff --git a/packages/frontend/src/workers/draw-blurhash.ts b/packages/frontend/src/workers/draw-blurhash.ts
new file mode 100644
index 000000000..5f2168a44
--- /dev/null
+++ b/packages/frontend/src/workers/draw-blurhash.ts
@@ -0,0 +1,15 @@
+import { render } from 'buraha';
+
+onmessage = (event) => {
+    // console.log(event.data);
+    if (!('id' in event.data && typeof event.data.id === 'string')) {
+        return;
+    }
+    if (!('hash' in event.data && typeof event.data.hash === 'string')) {
+        return;
+    }
+    const work = new OffscreenCanvas(event.data.width ?? 64, event.data.height ?? 64);
+    render(event.data.hash, work);
+    const bitmap = work.transferToImageBitmap();
+    postMessage({ id: event.data.id, bitmap });
+};
diff --git a/packages/frontend/src/workers/test-webgl2.ts b/packages/frontend/src/workers/test-webgl2.ts
new file mode 100644
index 000000000..4769524d9
--- /dev/null
+++ b/packages/frontend/src/workers/test-webgl2.ts
@@ -0,0 +1,7 @@
+const canvas = new OffscreenCanvas(1, 1);
+const gl = canvas.getContext('webgl2');
+if (gl) {
+    postMessage({ result: true });
+} else {
+    postMessage({ result: false });
+}
diff --git a/packages/frontend/src/workers/tsconfig.json b/packages/frontend/src/workers/tsconfig.json
new file mode 100644
index 000000000..8ee893046
--- /dev/null
+++ b/packages/frontend/src/workers/tsconfig.json
@@ -0,0 +1,5 @@
+{
+	"compilerOptions": {
+		"lib": ["esnext", "webworker"],
+	}
+}
diff --git a/packages/frontend/vite.config.ts b/packages/frontend/vite.config.ts
index 339761e78..3de9f9bdb 100644
--- a/packages/frontend/vite.config.ts
+++ b/packages/frontend/vite.config.ts
@@ -139,6 +139,10 @@ export function getConfig(): UserConfig {
 			},
 		},
 
+		worker: {
+			format: 'es',
+		},
+
 		test: {
 			environment: 'happy-dom',
 			deps: {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f98ed0f65..d5217b71f 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -657,15 +657,15 @@ importers:
       autosize:
         specifier: 6.0.1
         version: 6.0.1
-      blurhash:
-        specifier: 2.0.5
-        version: 2.0.5
       broadcast-channel:
         specifier: 4.20.2
         version: 4.20.2
       browser-image-resizer:
         specifier: github:misskey-dev/browser-image-resizer#v2.2.1-misskey.3
         version: github.com/misskey-dev/browser-image-resizer/0227e860621e55cbed0aabe6dc601096a7748c4a
+      buraha:
+        specifier: github:misskey-dev/buraha
+        version: github.com/misskey-dev/buraha/92b20c1ab15c5cb5a224cf3b1ecd4f6baca12b7c
       canvas-confetti:
         specifier: 1.6.0
         version: 1.6.0
@@ -20410,6 +20410,12 @@ packages:
     version: 2.2.1-misskey.3
     dev: false
 
+  github.com/misskey-dev/buraha/92b20c1ab15c5cb5a224cf3b1ecd4f6baca12b7c:
+    resolution: {tarball: https://codeload.github.com/misskey-dev/buraha/tar.gz/92b20c1ab15c5cb5a224cf3b1ecd4f6baca12b7c}
+    name: buraha
+    version: 0.0.0
+    dev: false
+
   github.com/misskey-dev/sharp-read-bmp/02d9dc189fa7df0c4bea09330be26741772dac01:
     resolution: {tarball: https://codeload.github.com/misskey-dev/sharp-read-bmp/tar.gz/02d9dc189fa7df0c4bea09330be26741772dac01}
     name: sharp-read-bmp