diff --git a/packages/frontend/src/components/MkDialog.vue b/packages/frontend/src/components/MkDialog.vue
index 2603a24193..c40ebfe10f 100644
--- a/packages/frontend/src/components/MkDialog.vue
+++ b/packages/frontend/src/components/MkDialog.vue
@@ -22,7 +22,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<i v-else-if="type === 'error'" :class="$style.iconInner" class="ti ti-circle-x"></i>
 			<i v-else-if="type === 'warning'" :class="$style.iconInner" class="ti ti-alert-triangle"></i>
 			<i v-else-if="type === 'info'" :class="$style.iconInner" class="ti ti-info-circle"></i>
-			<i v-else-if="type === 'question'" :class="$style.iconInner" class="ph-question ph-bold ph-lg"></i>
+			<i v-else-if="type === 'question'" :class="$style.iconInner" class="ti ti-help-circle"></i>
 			<MkLoading v-else-if="type === 'waiting'" :class="$style.iconInner" :em="true"/>
 		</div>
 		<header v-if="title" :class="$style.title"><Mfm :text="title"/></header>
diff --git a/packages/frontend/src/components/MkSignupDialog.form.vue b/packages/frontend/src/components/MkSignupDialog.form.vue
index 0018cf15f0..bd5fd979a5 100644
--- a/packages/frontend/src/components/MkSignupDialog.form.vue
+++ b/packages/frontend/src/components/MkSignupDialog.form.vue
@@ -15,7 +15,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 				<template #prefix><i class="ti ti-key"></i></template>
 			</MkInput>
 			<MkInput v-model="username" type="text" pattern="^[a-zA-Z0-9_]{1,20}$" :spellcheck="false" autocomplete="username" required data-cy-signup-username @update:modelValue="onChangeUsername">
-				<template #label>{{ i18n.ts.username }} <div v-tooltip:dialog="i18n.ts.usernameInfo" class="_button _help"><i class="ph-question ph-bold ph-lg"></i></div></template>
+				<template #label>{{ i18n.ts.username }} <div v-tooltip:dialog="i18n.ts.usernameInfo" class="_button _help"><i class="ti ti-help-circle"></i></div></template>
 				<template #prefix>@</template>
 				<template #suffix>@{{ host }}</template>
 				<template #caption>
@@ -30,7 +30,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 				</template>
 			</MkInput>
 			<MkInput v-if="instance.emailRequiredForSignup" v-model="email" :debounce="true" type="email" :spellcheck="false" required data-cy-signup-email @update:modelValue="onChangeEmail">
-				<template #label>{{ i18n.ts.emailAddress }} <div v-tooltip:dialog="i18n.ts._signup.emailAddressInfo" class="_button _help"><i class="ph-question ph-bold ph-lg"></i></div></template>
+				<template #label>{{ i18n.ts.emailAddress }} <div v-tooltip:dialog="i18n.ts._signup.emailAddressInfo" class="_button _help"><i class="ti ti-help-circle"></i></div></template>
 				<template #prefix><i class="ph-envelope ph-bold ph-lg"></i></template>
 				<template #caption>
 					<span v-if="emailState === 'wait'" style="color:#999"><MkLoading :em="true"/> {{ i18n.ts.checking }}</span>
diff --git a/packages/frontend/src/components/MkSwitch.vue b/packages/frontend/src/components/MkSwitch.vue
index 5672c8e9f7..a19b45448b 100644
--- a/packages/frontend/src/components/MkSwitch.vue
+++ b/packages/frontend/src/components/MkSwitch.vue
@@ -19,7 +19,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<span @click="toggle">
 				<slot name="label"></slot><slot></slot>
 			</span>
-			<span v-if="helpText" v-tooltip:dialog="helpText" class="_button _help" :class="$style.help"><i class="ph-question ph-bold ph-lg"></i></span>
+			<span v-if="helpText" v-tooltip:dialog="helpText" class="_button _help" :class="$style.help"><i class="ti ti-help-circle"></i></span>
 		</span>
 		<p :class="$style.caption"><slot name="caption"></slot></p>
 	</span>
diff --git a/packages/frontend/src/pages/contact.vue b/packages/frontend/src/pages/contact.vue
index b6cfebf229..bcdcf43275 100644
--- a/packages/frontend/src/pages/contact.vue
+++ b/packages/frontend/src/pages/contact.vue
@@ -35,6 +35,6 @@ import MkLink from '@/components/MkLink.vue';
 
 definePageMetadata(() => ({
 	title: i18n.ts.inquiry,
-	icon: 'ph-question ph-bold ph-lg',
+	icon: 'ti ti-help-circle',
 }));
 </script>
diff --git a/packages/frontend/src/pages/settings/2fa.vue b/packages/frontend/src/pages/settings/2fa.vue
index e4ce4480e8..537f03372f 100644
--- a/packages/frontend/src/pages/settings/2fa.vue
+++ b/packages/frontend/src/pages/settings/2fa.vue
@@ -32,7 +32,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 			<div v-else-if="!$i.twoFactorEnabled" class="_gaps_s">
 				<MkButton primary gradate @click="registerTOTP">{{ i18n.ts._2fa.registerTOTP }}</MkButton>
-				<MkLink url="https://misskey-hub.net/docs/for-users/stepped-guides/how-to-enable-2fa/" target="_blank"><i class="ph-question ph-bold ph-lg"></i> {{ i18n.ts.learnMore }}</MkLink>
+				<MkLink url="https://misskey-hub.net/docs/for-users/stepped-guides/how-to-enable-2fa/" target="_blank"><i class="ti ti-help-circle"></i> {{ i18n.ts.learnMore }}</MkLink>
 			</div>
 		</MkFolder>
 
diff --git a/packages/frontend/src/ui/_common_/common.ts b/packages/frontend/src/ui/_common_/common.ts
index 002cadd5a2..aeee1de816 100644
--- a/packages/frontend/src/ui/_common_/common.ts
+++ b/packages/frontend/src/ui/_common_/common.ts
@@ -82,7 +82,7 @@ export function openInstanceMenu(ev: MouseEvent) {
 	}, { type: 'divider' }, {
 		type: 'link',
 		text: i18n.ts.inquiry,
-		icon: 'ph-question ph-bold ph-lg',
+		icon: 'ti ti-help-circle',
 		to: '/contact',
 	}, (instance.impressumUrl) ? {
 		text: i18n.ts.impressum,
diff --git a/packages/frontend/vite.config.ts b/packages/frontend/vite.config.ts
index 22ce598f97..2e48aea328 100644
--- a/packages/frontend/vite.config.ts
+++ b/packages/frontend/vite.config.ts
@@ -174,6 +174,7 @@ export function getConfig(): UserConfig {
 					'ti ti-chevron-up': 'ph-caret-up ph-bold ph-lg',
  					'ti ti-chevron-down': 'ph-caret-down ph-bold ph-lg',
  					'ti ti-caret-down': 'ph-caret-down ph-bold ph-lg',
+					'ti ti-help-circle': 'ph-question ph-bold ph-lg',
 				},
 			}),
 			...process.env.NODE_ENV === 'production'