diff --git a/packages/frontend/src/components/MkPostForm.vue b/packages/frontend/src/components/MkPostForm.vue
index 2d8a341d50..e2f1ab6f3b 100644
--- a/packages/frontend/src/components/MkPostForm.vue
+++ b/packages/frontend/src/components/MkPostForm.vue
@@ -706,6 +706,8 @@ function onDrop(ev: DragEvent): void {
 function saveDraft(auto = true) {
 	if (props.instant || props.mock) return;
 
+	if (auto && defaultStore.state.draftSavingBehavior !== 'auto') return;
+
 	if (!auto) {
 		// 手動での保存の場合は自動保存したものを削除した上で保存
 		noteDrafts.remove(draftType.value, $i.id, 'default', draftAuxId.value as string);
@@ -952,6 +954,18 @@ function cancel() {
 	emit('cancel');
 }
 
+async function closed() {
+	if (defaultStore.state.draftSavingBehavior === 'manual' && text.value !== '') {
+		os.confirm({
+			type: 'question',
+			text: i18n.ts.saveConfirm,
+		}).then(({ canceled }) => {
+			if (canceled) return;
+			saveDraft(false);
+		});
+	}
+}
+
 function insertMention() {
 	os.selectUser({ localOnly: localOnly.value, includeSelf: true }).then(user => {
 		insertTextAtCursor(textareaEl.value, '@' + Misskey.acct.toString(user) + ' ');
@@ -1109,6 +1123,7 @@ onMounted(() => {
 
 defineExpose({
 	clear,
+	closed,
 });
 </script>
 
diff --git a/packages/frontend/src/components/MkPostFormDialog.vue b/packages/frontend/src/components/MkPostFormDialog.vue
index d3de1af75e..075635d67e 100644
--- a/packages/frontend/src/components/MkPostFormDialog.vue
+++ b/packages/frontend/src/components/MkPostFormDialog.vue
@@ -50,6 +50,7 @@ function onPosted() {
 }
 
 function onModalClosed() {
+	form.value?.closed();
 	emit('closed');
 }
 </script>
diff --git a/packages/frontend/src/store.ts b/packages/frontend/src/store.ts
index ecd243f681..c20c945aef 100644
--- a/packages/frontend/src/store.ts
+++ b/packages/frontend/src/store.ts
@@ -101,8 +101,27 @@ export const defaultStore = markRaw(new Storage('base', {
 	defaultHomeNoteLocalOnly: {
 		where: 'account',
 		default: false,
+	},	defaultFollowersNoteLocalOnly: {
+		where: 'account',
+		default: false,
 	},
-	defaultFollowersNoteLocalOnly: {
+	draftSavingBehavior: {
+		where: 'account',
+		default: 'auto' as 'auto' | 'manual',
+	},
+	rememberNoteVisibility: {
+		where: 'account',
+		default: false,
+	},
+	rememberReactionAcceptance: {
+		where: 'account',
+		default: false,
+	},
+	defaultNoteVisibility: {
+		where: 'account',
+		default: 'home',
+	},
+	defaultNoteLocalOnly: {
 		where: 'account',
 		default: false,
 	},