diff --git a/package.json b/package.json
index 4b6b7b4f4..2448da908 100644
--- a/package.json
+++ b/package.json
@@ -154,7 +154,6 @@
 		"http-proxy-agent": "4.0.1",
 		"http-signature": "1.3.5",
 		"https-proxy-agent": "5.0.0",
-		"idb-keyval": "3.2.0",
 		"insert-text-at-cursor": "0.3.0",
 		"is-root": "2.1.0",
 		"is-svg": "4.2.1",
diff --git a/src/client/db.ts b/src/client/db.ts
deleted file mode 100644
index 3000a0c96..000000000
--- a/src/client/db.ts
+++ /dev/null
@@ -1,68 +0,0 @@
-import { Store } from 'idb-keyval';
-// Provide functions from idb-keyval
-export { get, set, del, clear, keys } from 'idb-keyval';
-
-//#region Construct DB
-export const clientDb = {
-	i18n: new Store('MisskeyClient', 'i18n')
-};
-//#endregion
-
-//#region Provide some tool functions
-function openTransaction(store: Store, mode: IDBTransactionMode): Promise<IDBTransaction>{
-	return store._dbp.then(db => db.transaction(store.storeName, mode));
-}
-
-export function entries(store: Store): Promise<[IDBValidKey, unknown][]> {
-	const entries: [IDBValidKey, unknown][] = [];
-
-	return store._withIDBStore('readonly', store => {
-		store.openCursor().onsuccess = function () {
-			if (!this.result) return;
-			entries.push([this.result.key, this.result.value]);
-			this.result.continue();
-		};
-	}).then(() => entries);
-}
-
-export async function bulkGet(keys: IDBValidKey[], store: Store): Promise<[IDBValidKey, unknown][]> {
-	const valPromises: Promise<[IDBValidKey, unknown]>[] = [];
-
-	const tx = await openTransaction(store, 'readwrite');
-	const st = tx.objectStore(store.storeName);
-	for (const key of keys) {
-		valPromises.push(new Promise((resolve, reject) => {
-			const getting = st.get(key);
-			getting.onsuccess = function (e) {
-				return resolve([key, this.result]);
-			};
-			getting.onerror = function (e) {
-				return reject(this.error);
-			};
-		}));
-	}
-	return new Promise((resolve, reject) => {
-		tx.oncomplete = () => resolve(Promise.all(valPromises));
-		tx.abort = tx.onerror = () => reject(tx.error);
-	});
-}
-
-export async function bulkSet(map: [IDBValidKey, any][], store: Store): Promise<void> {
-	const tx = await openTransaction(store, 'readwrite');
-	const st = tx.objectStore(store.storeName);
-	for (const [key, value] of map) {
-		st.put(value, key);
-	}
-	return new Promise((resolve, reject) => {
-		tx.oncomplete = () => resolve();
-		tx.abort = tx.onerror = () => reject(tx.error);
-	});
-}
-
-export function count(store: Store): Promise<number> {
-	let req: IDBRequest<number>;
-	return store._withIDBStore('readonly', store => {
-		req = store.count();
-	}).then(() => req.result);
-}
-//#endregion
diff --git a/src/client/pages/settings/deck.vue b/src/client/pages/settings/deck.vue
index 4b672af82..7b6824d10 100644
--- a/src/client/pages/settings/deck.vue
+++ b/src/client/pages/settings/deck.vue
@@ -36,8 +36,6 @@ import FormSelect from '@/components/form/select.vue';
 import FormRadios from '@/components/form/radios.vue';
 import FormBase from '@/components/form/base.vue';
 import FormGroup from '@/components/form/group.vue';
-import { clientDb, set } from '@/db';
-import * as os from '@/os';
 import { deckStore } from '@/ui/deck/deck-store';
 
 export default defineComponent({
diff --git a/src/client/pages/settings/general.vue b/src/client/pages/settings/general.vue
index e6bb1b8a7..8869644ce 100644
--- a/src/client/pages/settings/general.vue
+++ b/src/client/pages/settings/general.vue
@@ -77,8 +77,6 @@
 	</FormSelect>
 
 	<FormLink to="/settings/deck">{{ $ts.deck }}</FormLink>
-
-	<FormButton @click="cacheClear()" danger>{{ $ts.cacheClear }}</FormButton>
 </FormBase>
 </template>
 
@@ -94,8 +92,6 @@ import FormLink from '@/components/form/link.vue';
 import FormButton from '@/components/form/button.vue';
 import MkLink from '@/components/link.vue';
 import { langs } from '@/config';
-import { clientDb, set } from '@/db';
-import * as os from '@/os';
 import { defaultStore } from '@/store';
 import { ColdDeviceStorage } from '@/store';
 
@@ -149,14 +145,7 @@ export default defineComponent({
 	watch: {
 		lang() {
 			localStorage.setItem('lang', this.lang);
-
-			return set('_version_', `changeLang-${(new Date()).toJSON()}`, clientDb.i18n)
-				.then(() => location.reload())
-				.catch(() => {
-					os.dialog({
-						type: 'error',
-					});
-				});
+			location.reload();
 		},
 
 		fontSize() {
@@ -185,23 +174,5 @@ export default defineComponent({
 	mounted() {
 		this.$emit('info', this.INFO);
 	},
-
-	methods: {
-		cacheClear() {
-			// Clear cache (service worker)
-			try {
-				navigator.serviceWorker.controller.postMessage('clear');
-
-				navigator.serviceWorker.getRegistrations().then(registrations => {
-					for (const registration of registrations) registration.unregister();
-				});
-			} catch (e) {
-				console.error(e);
-			}
-
-			// Force reload
-			location.reload(true);
-		}
-	}
 });
 </script>
diff --git a/yarn.lock b/yarn.lock
index 7e3088744..96fd4e7e6 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4955,11 +4955,6 @@ icss-utils@^5.0.0:
   resolved "https://registry.yarnpkg.com/icss-utils/-/icss-utils-5.0.0.tgz#03ed56c3accd32f9caaf1752ebf64ef12347bb84"
   integrity sha512-aF2Cf/CkEZrI/vsu5WI/I+akFgdbwQHVE9YRZxATrhH4PVIe6a3BIjwjEcW+z+jP/hNh+YvM3lAAn1wJQ6opSg==
 
-idb-keyval@3.2.0:
-  version "3.2.0"
-  resolved "https://registry.yarnpkg.com/idb-keyval/-/idb-keyval-3.2.0.tgz#cbbf354deb5684b6cdc84376294fc05932845bd6"
-  integrity sha512-slx8Q6oywCCSfKgPgL0sEsXtPVnSbTLWpyiDcu6msHOyKOLari1TD1qocXVCft80umnkk3/Qqh3lwoFt8T/BPQ==
-
 ieee754@1.1.13, ieee754@^1.1.13, ieee754@^1.1.4:
   version "1.1.13"
   resolved "https://registry.yarnpkg.com/ieee754/-/ieee754-1.1.13.tgz#ec168558e95aa181fd87d37f55c32bbcb6708b84"