diff --git a/cypress/e2e/widgets.cy.js b/cypress/e2e/widgets.cy.js
index 271917889e..7d2039ff91 100644
--- a/cypress/e2e/widgets.cy.js
+++ b/cypress/e2e/widgets.cy.js
@@ -39,7 +39,7 @@ describe('After user signed in', () => {
 			cy.get('.mk-widget-select select').select(widgetName, { force: true });
 			cy.get('.data-cy-bg._modalBg.data-cy-transparent').click({ multiple: true, force: true });
 			cy.get('.mk-widget-add').click({ force: true });
-			cy.get(`.mkw-${widgetName}`).should('exist');
+			cy.get(`.data-cy-mkw-${widgetName}`).should('exist');
 		});
 	}
 
diff --git a/packages/frontend/src/widgets/WidgetActivity.vue b/packages/frontend/src/widgets/WidgetActivity.vue
index 1834036789..da1cab6f88 100644
--- a/packages/frontend/src/widgets/WidgetActivity.vue
+++ b/packages/frontend/src/widgets/WidgetActivity.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" :naked="widgetProps.transparent" class="mkw-activity">
+<MkContainer :show-header="widgetProps.showHeader" :naked="widgetProps.transparent" class="mkw-activity data-cy-mkw-activity">
 	<template #icon><i class="ti ti-chart-line"></i></template>
 	<template #header>{{ i18n.ts._widgets.activity }}</template>
 	<template #func="{ buttonStyleClass }"><button class="_button" :class="buttonStyleClass" @click="toggleView()"><i class="ti ti-selector"></i></button></template>
diff --git a/packages/frontend/src/widgets/WidgetAichan.vue b/packages/frontend/src/widgets/WidgetAichan.vue
index ab5b375ae4..1bb3089d16 100644
--- a/packages/frontend/src/widgets/WidgetAichan.vue
+++ b/packages/frontend/src/widgets/WidgetAichan.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :naked="widgetProps.transparent" :show-header="false" class="mkw-aichan">
+<MkContainer :naked="widgetProps.transparent" :show-header="false" class="mkw-aichan data-cy-mkw-aichan">
 	<iframe ref="live2d" class="dedjhjmo" src="https://misskey-dev.github.io/mascot-web/?scale=1.5&y=1.1&eyeY=100" @click="touched"></iframe>
 </MkContainer>
 </template>
diff --git a/packages/frontend/src/widgets/WidgetAiscript.vue b/packages/frontend/src/widgets/WidgetAiscript.vue
index 2e49a354ef..141626955e 100644
--- a/packages/frontend/src/widgets/WidgetAiscript.vue
+++ b/packages/frontend/src/widgets/WidgetAiscript.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" class="mkw-aiscript">
+<MkContainer :show-header="widgetProps.showHeader" class="mkw-aiscript data-cy-mkw-aiscript">
 	<template #icon><i class="ti ti-terminal-2"></i></template>
 	<template #header>{{ i18n.ts._widgets.aiscript }}</template>
 
diff --git a/packages/frontend/src/widgets/WidgetButton.vue b/packages/frontend/src/widgets/WidgetButton.vue
index f65b115cc0..63e8e485e1 100644
--- a/packages/frontend/src/widgets/WidgetButton.vue
+++ b/packages/frontend/src/widgets/WidgetButton.vue
@@ -1,5 +1,5 @@
 <template>
-<div class="mkw-button">
+<div class="mkw-button data-cy-mkw-button">
 	<MkButton :primary="widgetProps.colored" full @click="run">
 		{{ widgetProps.label }}
 	</MkButton>
diff --git a/packages/frontend/src/widgets/WidgetCalendar.vue b/packages/frontend/src/widgets/WidgetCalendar.vue
index 1edadb1871..fe31e10215 100644
--- a/packages/frontend/src/widgets/WidgetCalendar.vue
+++ b/packages/frontend/src/widgets/WidgetCalendar.vue
@@ -1,5 +1,5 @@
 <template>
-<div :class="[$style.root, { _panel: !widgetProps.transparent }]">
+<div :class="[$style.root, { _panel: !widgetProps.transparent }]" class="data-cy-mkw-calendar">
 	<div :class="[$style.calendar, { [$style.isHoliday]: isHoliday }]">
 		<p :class="$style.monthAndYear">
 			<span :class="$style.year">{{ $t('yearX', { year }) }}</span>
diff --git a/packages/frontend/src/widgets/WidgetClock.vue b/packages/frontend/src/widgets/WidgetClock.vue
index dc99b6631e..7f9c96b93b 100644
--- a/packages/frontend/src/widgets/WidgetClock.vue
+++ b/packages/frontend/src/widgets/WidgetClock.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :naked="widgetProps.transparent" :show-header="false" class="mkw-clock">
+<MkContainer :naked="widgetProps.transparent" :show-header="false" class="mkw-clock data-cy-mkw-clock">
 	<div class="vubelbmv" :class="widgetProps.size">
 		<div v-if="widgetProps.label === 'tz' || widgetProps.label === 'timeAndTz'" class="_monospace label a abbrev">{{ tzAbbrev }}</div>
 		<MkAnalogClock
diff --git a/packages/frontend/src/widgets/WidgetDigitalClock.vue b/packages/frontend/src/widgets/WidgetDigitalClock.vue
index b70b2767b3..0f9c46f1c7 100644
--- a/packages/frontend/src/widgets/WidgetDigitalClock.vue
+++ b/packages/frontend/src/widgets/WidgetDigitalClock.vue
@@ -1,5 +1,5 @@
 <template>
-<div class="_monospace" :class="[$style.root, { _panel: !widgetProps.transparent }]" :style="{ fontSize: `${widgetProps.fontSize}em` }">
+<div class="data-cy-mkw-digitalClock _monospace" :class="[$style.root, { _panel: !widgetProps.transparent }]" :style="{ fontSize: `${widgetProps.fontSize}em` }">
 	<div v-if="widgetProps.showLabel" :class="$style.label">{{ tzAbbrev }}</div>
 	<div>
 		<MkDigitalClock :show-ms="widgetProps.showMs" :offset="tzOffset"/>
diff --git a/packages/frontend/src/widgets/WidgetFederation.vue b/packages/frontend/src/widgets/WidgetFederation.vue
index ea82b0c12d..806c5d1801 100644
--- a/packages/frontend/src/widgets/WidgetFederation.vue
+++ b/packages/frontend/src/widgets/WidgetFederation.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" :foldable="foldable" :scrollable="scrollable" class="mkw-federation">
+<MkContainer :show-header="widgetProps.showHeader" :foldable="foldable" :scrollable="scrollable" class="mkw-federation data-cy-mkw-federation">
 	<template #icon><i class="ti ti-whirl"></i></template>
 	<template #header>{{ i18n.ts._widgets.federation }}</template>
 
diff --git a/packages/frontend/src/widgets/WidgetJobQueue.vue b/packages/frontend/src/widgets/WidgetJobQueue.vue
index 9f19c51825..e19cbb185a 100644
--- a/packages/frontend/src/widgets/WidgetJobQueue.vue
+++ b/packages/frontend/src/widgets/WidgetJobQueue.vue
@@ -1,5 +1,5 @@
 <template>
-<div class="mkw-jobQueue _monospace" :class="{ _panel: !widgetProps.transparent }">
+<div class="mkw-jobQueue data-cy-mkw-jobQueue _monospace" :class="{ _panel: !widgetProps.transparent }">
 	<div class="inbox">
 		<div class="label">Inbox queue<i v-if="current.inbox.waiting > 0" class="ti ti-alert-triangle icon"></i></div>
 		<div class="values">
diff --git a/packages/frontend/src/widgets/WidgetMemo.vue b/packages/frontend/src/widgets/WidgetMemo.vue
index 8523aee544..689dbe0e6f 100644
--- a/packages/frontend/src/widgets/WidgetMemo.vue
+++ b/packages/frontend/src/widgets/WidgetMemo.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" class="mkw-memo">
+<MkContainer :show-header="widgetProps.showHeader" class="mkw-memo data-cy-mkw-memo">
 	<template #icon><i class="ti ti-note"></i></template>
 	<template #header>{{ i18n.ts._widgets.memo }}</template>
 
diff --git a/packages/frontend/src/widgets/WidgetNotifications.vue b/packages/frontend/src/widgets/WidgetNotifications.vue
index 89f3114b85..e4ae37950c 100644
--- a/packages/frontend/src/widgets/WidgetNotifications.vue
+++ b/packages/frontend/src/widgets/WidgetNotifications.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :style="`height: ${widgetProps.height}px;`" :show-header="widgetProps.showHeader" :scrollable="true" class="mkw-notifications">
+<MkContainer :style="`height: ${widgetProps.height}px;`" :show-header="widgetProps.showHeader" :scrollable="true" class="mkw-notifications data-cy-mkw-notifications">
 	<template #icon><i class="ti ti-bell"></i></template>
 	<template #header>{{ i18n.ts.notifications }}</template>
 	<template #func="{ buttonStyleClass }"><button class="_button" :class="buttonStyleClass" @click="configureNotification()"><i class="ti ti-settings"></i></button></template>
diff --git a/packages/frontend/src/widgets/WidgetOnlineUsers.vue b/packages/frontend/src/widgets/WidgetOnlineUsers.vue
index e9ab79b111..705be1c8a7 100644
--- a/packages/frontend/src/widgets/WidgetOnlineUsers.vue
+++ b/packages/frontend/src/widgets/WidgetOnlineUsers.vue
@@ -1,5 +1,5 @@
 <template>
-<div class="mkw-onlineUsers" :class="{ _panel: !widgetProps.transparent, pad: !widgetProps.transparent }">
+<div class="mkw-onlineUsers data-cy-mkw-onlineUsers" :class="{ _panel: !widgetProps.transparent, pad: !widgetProps.transparent }">
 	<I18n v-if="onlineUsersCount" :src="i18n.ts.onlineUsersCount" text-tag="span" class="text">
 		<template #n><b>{{ onlineUsersCount }}</b></template>
 	</I18n>
diff --git a/packages/frontend/src/widgets/WidgetPhotos.vue b/packages/frontend/src/widgets/WidgetPhotos.vue
index 4e55bb9927..2d6f0a5ec7 100644
--- a/packages/frontend/src/widgets/WidgetPhotos.vue
+++ b/packages/frontend/src/widgets/WidgetPhotos.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" :naked="widgetProps.transparent" :class="$style.root" :data-transparent="widgetProps.transparent ? true : null" class="mkw-photos">
+<MkContainer :show-header="widgetProps.showHeader" :naked="widgetProps.transparent" :class="$style.root" :data-transparent="widgetProps.transparent ? true : null" class="mkw-photos data-cy-mkw-photos">
 	<template #icon><i class="ti ti-camera"></i></template>
 	<template #header>{{ i18n.ts._widgets.photos }}</template>
 
diff --git a/packages/frontend/src/widgets/WidgetPostForm.vue b/packages/frontend/src/widgets/WidgetPostForm.vue
index f1708775ba..54226c1dbf 100644
--- a/packages/frontend/src/widgets/WidgetPostForm.vue
+++ b/packages/frontend/src/widgets/WidgetPostForm.vue
@@ -1,5 +1,5 @@
 <template>
-<XPostForm class="_panel mkw-postForm" :fixed="true" :autofocus="false"/>
+<XPostForm class="_panel mkw-postForm data-cy-mkw-postForm" :fixed="true" :autofocus="false"/>
 </template>
 
 <script lang="ts" setup>
diff --git a/packages/frontend/src/widgets/WidgetRss.vue b/packages/frontend/src/widgets/WidgetRss.vue
index a25bd67aae..e212003f34 100644
--- a/packages/frontend/src/widgets/WidgetRss.vue
+++ b/packages/frontend/src/widgets/WidgetRss.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" class="mkw-rss">
+<MkContainer :show-header="widgetProps.showHeader" class="mkw-rss data-cy-mkw-rss">
 	<template #icon><i class="ti ti-rss"></i></template>
 	<template #header>RSS</template>
 	<template #func="{ buttonStyleClass }"><button class="_button" :class="buttonStyleClass" @click="configure"><i class="ti ti-settings"></i></button></template>
diff --git a/packages/frontend/src/widgets/WidgetSlideshow.vue b/packages/frontend/src/widgets/WidgetSlideshow.vue
index 2c937d85c5..c2ad23b311 100644
--- a/packages/frontend/src/widgets/WidgetSlideshow.vue
+++ b/packages/frontend/src/widgets/WidgetSlideshow.vue
@@ -1,5 +1,5 @@
 <template>
-<div class="kvausudm _panel mkw-slideshow" :style="{ height: widgetProps.height + 'px' }">
+<div class="kvausudm _panel mkw-slideshow data-cy-mkw-slideshow" :style="{ height: widgetProps.height + 'px' }">
 	<div @click="choose">
 		<p v-if="widgetProps.folderId == null">
 			{{ i18n.ts.folder }}
diff --git a/packages/frontend/src/widgets/WidgetTimeline.vue b/packages/frontend/src/widgets/WidgetTimeline.vue
index 8618dbc2ea..e6abf561b9 100644
--- a/packages/frontend/src/widgets/WidgetTimeline.vue
+++ b/packages/frontend/src/widgets/WidgetTimeline.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" :style="`height: ${widgetProps.height}px;`" :scrollable="true" class="mkw-timeline">
+<MkContainer :show-header="widgetProps.showHeader" :style="`height: ${widgetProps.height}px;`" :scrollable="true" class="mkw-timeline data-cy-mkw-timeline">
 	<template #icon>
 		<i v-if="widgetProps.src === 'home'" class="ti ti-home"></i>
 		<i v-else-if="widgetProps.src === 'local'" class="ti ti-planet"></i>
diff --git a/packages/frontend/src/widgets/WidgetTrends.vue b/packages/frontend/src/widgets/WidgetTrends.vue
index 94849fdba4..76651c1d0f 100644
--- a/packages/frontend/src/widgets/WidgetTrends.vue
+++ b/packages/frontend/src/widgets/WidgetTrends.vue
@@ -1,5 +1,5 @@
 <template>
-<MkContainer :show-header="widgetProps.showHeader" class="mkw-trends">
+<MkContainer :show-header="widgetProps.showHeader" class="mkw-trends data-cy-mkw-trends">
 	<template #icon><i class="ti ti-hash"></i></template>
 	<template #header>{{ i18n.ts._widgets.trends }}</template>
 
diff --git a/packages/frontend/src/widgets/server-metric/index.vue b/packages/frontend/src/widgets/server-metric/index.vue
index b7537e1957..f79858db26 100644
--- a/packages/frontend/src/widgets/server-metric/index.vue
+++ b/packages/frontend/src/widgets/server-metric/index.vue
@@ -4,7 +4,7 @@
 	<template #header>{{ i18n.ts._widgets.serverMetric }}</template>
 	<template #func="{ buttonStyleClass }"><button class="_button" :class="buttonStyleClass" @click="toggleView()"><i class="ti ti-selector"></i></button></template>
 
-	<div v-if="meta" class="mkw-serverMetric">
+	<div v-if="meta" class="mkw-serverMetric data-cy-mkw-serverMetric">
 		<XCpuMemory v-if="widgetProps.view === 0" :connection="connection" :meta="meta"/>
 		<XNet v-else-if="widgetProps.view === 1" :connection="connection" :meta="meta"/>
 		<XCpu v-else-if="widgetProps.view === 2" :connection="connection" :meta="meta"/>