diff --git a/packages/client/@types/window.d.ts b/packages/client/@types/window.d.ts
new file mode 100644
index 0000000000..1ae20c0d20
--- /dev/null
+++ b/packages/client/@types/window.d.ts
@@ -0,0 +1,6 @@
+declare global {
+	interface Window {
+		__misskey_input_ref__?: HTMLInputElement | null;
+	}
+}
+export type {};
diff --git a/packages/client/src/components/MkDialog.vue b/packages/client/src/components/MkDialog.vue
index c1f8f581a7..a345f7dcea 100644
--- a/packages/client/src/components/MkDialog.vue
+++ b/packages/client/src/components/MkDialog.vue
@@ -216,25 +216,32 @@ interface Input {
 		| "paragraph";
 	placeholder?: string | null;
 	autocomplete?: string;
-	default: string | number | null;
+	default?: string | number | null;
 	minLength?: number;
 	maxLength?: number;
 }
 
-interface Select {
-	items: {
-		value: string;
-		text: string;
-	}[];
-	groupedItems: {
-		label: string;
-		items: {
-			value: string;
-			text: string;
-		}[];
-	}[];
-	default: string | null;
-}
+type Select = {
+	default?: string | null;
+} & (
+	| {
+			items: {
+				value: string;
+				text: string;
+			}[];
+			groupedItems?: undefined;
+	  }
+	| {
+			items?: undefined;
+			groupedItems: {
+				label: string;
+				items: {
+					value: string;
+					text: string;
+				}[];
+			}[];
+	  }
+);
 
 const props = withDefaults(
 	defineProps<{
diff --git a/packages/client/src/components/MkMenu.vue b/packages/client/src/components/MkMenu.vue
index c778f0f6f1..e92305d8f3 100644
--- a/packages/client/src/components/MkMenu.vue
+++ b/packages/client/src/components/MkMenu.vue
@@ -254,8 +254,7 @@ const isActive = ref();
 watch(
 	() => props.items,
 	() => {
-		// FIXME: what's this?
-		const items: (MenuItem | MenuPending)[] = [...props.items].filter(
+		const items: (MenuItem | MenuPending)[] = props.items.filter(
 			(item) => item !== undefined,
 		);
 
diff --git a/packages/client/src/components/MkUrlPreview.vue b/packages/client/src/components/MkUrlPreview.vue
index e72bdd704e..95e46ee2cc 100644
--- a/packages/client/src/components/MkUrlPreview.vue
+++ b/packages/client/src/components/MkUrlPreview.vue
@@ -181,10 +181,10 @@ function adjustTweetHeight(message: any) {
 	if (height) tweetHeight.value = height;
 }
 
-(window as any).addEventListener("message", adjustTweetHeight);
+window.addEventListener("message", adjustTweetHeight);
 
 onUnmounted(() => {
-	(window as any).removeEventListener("message", adjustTweetHeight);
+	window.removeEventListener("message", adjustTweetHeight);
 });
 </script>
 
diff --git a/packages/client/src/components/MkWaitingDialog.vue b/packages/client/src/components/MkWaitingDialog.vue
index c35023adcb..18cec42a49 100644
--- a/packages/client/src/components/MkWaitingDialog.vue
+++ b/packages/client/src/components/MkWaitingDialog.vue
@@ -13,7 +13,7 @@
 			]"
 		>
 			<i
-				v-if="success"
+				v-if="unref(success)"
 				:class="[$style.icon, $style.success, iconify('ph-check')]"
 			></i>
 			<MkLoading
@@ -29,15 +29,15 @@
 </template>
 
 <script lang="ts" setup>
-import { shallowRef, watch } from "vue";
+import { MaybeRef, shallowRef, watch, unref } from "vue";
 import MkModal from "@/components/MkModal.vue";
 import iconify from "@/scripts/icon";
 
 const modal = shallowRef<InstanceType<typeof MkModal>>();
 
 const props = defineProps<{
-	success: boolean;
-	showing: boolean;
+	success: MaybeRef<boolean>;
+	showing: MaybeRef<boolean>;
 	text?: string;
 }>();
 
diff --git a/packages/client/src/os.ts b/packages/client/src/os.ts
index b7a17097e3..0bdacd3adb 100644
--- a/packages/client/src/os.ts
+++ b/packages/client/src/os.ts
@@ -1,7 +1,7 @@
 // TODO: なんでもかんでもos.tsに突っ込むのやめたいのでよしなに分割する
 
 import { EventEmitter } from "eventemitter3";
-import { type entities, api as firefishApi } from "firefish-js";
+import { type entities, api as firefishApi, type Endpoints } from "firefish-js";
 import insertTextAtCursor from "insert-text-at-cursor";
 import type { Component, Ref } from "vue";
 import { defineAsyncComponent, markRaw, ref } from "vue";
@@ -13,7 +13,7 @@ import MkWaitingDialog from "@/components/MkWaitingDialog.vue";
 import { apiUrl, url } from "@/config";
 import { me } from "@/me";
 import type { MenuItem } from "@/types/menu";
-import type { FormItemType, GetFormResultType } from "@/types/form";
+import type { Form, GetFormResultType } from "@/types/form";
 
 export const pendingApiRequestsCount = ref(0);
 
@@ -52,7 +52,7 @@ export const api = ((
 				if (res.status === 200) {
 					resolve(body);
 				} else if (res.status === 204) {
-					resolve();
+					resolve(undefined);
 				} else {
 					reject(body.error);
 				}
@@ -67,7 +67,7 @@ export const api = ((
 
 export const apiGet = ((
 	endpoint: string,
-	data: Record<string, any> = {},
+	data: URLSearchParams | string | string[][] | Record<string, string> = {},
 	token?: string | null | undefined,
 ) => {
 	pendingApiRequestsCount.value++;
@@ -97,7 +97,7 @@ export const apiGet = ((
 				if (res.status === 200) {
 					resolve(body);
 				} else if (res.status === 204) {
-					resolve();
+					resolve(undefined);
 				} else {
 					reject(body.error);
 				}
@@ -111,15 +111,15 @@ export const apiGet = ((
 }) as typeof apiClient.request;
 
 export const apiWithDialog = ((
-	endpoint: string,
-	data: Record<string, any> = {},
+	endpoint: keyof Endpoints,
+	data: Record<string, unknown> = {},
 	token?: string | null | undefined,
 ) => {
 	const promise = api(endpoint, data, token);
 	promiseDialog(promise, null, (err) => {
 		alert({
 			type: "error",
-			text: err.message + "\n" + (err as any).id,
+			text: `${err.message}\n${err.id}`,
 		});
 	});
 
@@ -129,7 +129,7 @@ export const apiWithDialog = ((
 export function promiseDialog<T>(
 	promise: Promise<T>,
 	onSuccess?: ((res: T) => void) | null,
-	onFailure?: ((err: Error) => void) | null,
+	onFailure?: ((err: firefishApi.APIError) => void) | null,
 	text?: string,
 ): Promise<T> {
 	const showing = ref(true);
@@ -294,7 +294,7 @@ export function alert(props: {
 	text?: string | null;
 	isPlaintext?: boolean;
 }): Promise<void> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		if (props.text == null && props.type === "error") {
 			props.text = i18n.ts.somethingHappened;
 		}
@@ -319,7 +319,7 @@ export function confirm(props: {
 	cancelText?: string;
 	isPlaintext?: boolean;
 }): Promise<{ canceled: boolean }> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			MkDialog,
 			{
@@ -342,7 +342,7 @@ export function yesno(props: {
 	text?: string | null;
 	isPlaintext?: boolean;
 }): Promise<{ canceled: boolean }> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkDialog.vue"),
@@ -374,13 +374,13 @@ export function inputText(props: {
 	minLength?: number;
 	maxLength?: number;
 }): Promise<
-	| { canceled: true; result: undefined }
+	| { canceled: true; result?: undefined }
 	| {
 			canceled: false;
 			result: string;
 	  }
 > {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			MkDialog,
 			{
@@ -397,7 +397,14 @@ export function inputText(props: {
 			},
 			{
 				done: (result) => {
-					resolve(result || { canceled: true });
+					if (result.canceled) {
+						resolve({ canceled: true });
+					} else {
+						resolve({
+							canceled: false,
+							result: String(result.result),
+						});
+					}
 				},
 			},
 			"closed",
@@ -411,13 +418,13 @@ export function inputParagraph(props: {
 	placeholder?: string | null;
 	default?: string | null;
 }): Promise<
-	| { canceled: true; result: undefined }
+	| { canceled: true; result?: undefined }
 	| {
 			canceled: false;
 			result: string;
 	  }
 > {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkDialog.vue"),
@@ -435,7 +442,14 @@ export function inputParagraph(props: {
 			},
 			{
 				done: (result) => {
-					resolve(result || { canceled: true });
+					if (result.canceled) {
+						resolve({ canceled: true });
+					} else {
+						resolve({
+							canceled: false,
+							result: String(result.result),
+						});
+					}
 				},
 			},
 			"closed",
@@ -450,13 +464,13 @@ export function inputNumber(props: {
 	default?: number | null;
 	autocomplete?: string;
 }): Promise<
-	| { canceled: true; result: undefined }
+	| { canceled: true; result?: undefined }
 	| {
 			canceled: false;
 			result: number;
 	  }
 > {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkDialog.vue"),
@@ -475,7 +489,14 @@ export function inputNumber(props: {
 			},
 			{
 				done: (result) => {
-					resolve(result || { canceled: true });
+					if (result.canceled) {
+						resolve({ canceled: true });
+					} else {
+						resolve({
+							canceled: false,
+							result: Number(result.result),
+						});
+					}
 				},
 			},
 			"closed",
@@ -487,15 +508,16 @@ export function inputDate(props: {
 	title?: string | null;
 	text?: string | null;
 	placeholder?: string | null;
-	default?: Date | null;
+	default?: Date | string | null;
 }): Promise<
-	| { canceled: true; result: undefined }
+	| { canceled: true; result?: undefined }
 	| {
 			canceled: false;
 			result: Date;
 	  }
 > {
-	return new Promise((resolve, reject) => {
+	props.default ??= new Date();
+	return new Promise((resolve, _reject) => {
 		popup(
 			MkDialog,
 			{
@@ -504,7 +526,10 @@ export function inputDate(props: {
 				input: {
 					type: "date",
 					placeholder: props.placeholder,
-					default: props.default,
+					default:
+						props.default instanceof Date
+							? props.default.toISOString().slice(0, 10)
+							: props.default,
 				},
 			},
 			{
@@ -512,7 +537,7 @@ export function inputDate(props: {
 					resolve(
 						result
 							? {
-									result: new Date(result.result),
+									result: new Date(result.result as string | number),
 									canceled: false,
 								}
 							: { canceled: true },
@@ -524,7 +549,7 @@ export function inputDate(props: {
 	});
 }
 
-export function select<C = any>(
+export function select<C extends string>(
 	props: {
 		title?: string | null;
 		text?: string | null;
@@ -535,8 +560,10 @@ export function select<C = any>(
 					value: C;
 					text: string;
 				}[];
+				groupedItems?: undefined;
 		  }
 		| {
+				items?: undefined;
 				groupedItems: {
 					label: string;
 					items: {
@@ -547,27 +574,35 @@ export function select<C = any>(
 		  }
 	),
 ): Promise<
-	| { canceled: true; result: undefined }
+	| { canceled: true; result?: undefined }
 	| {
 			canceled: false;
 			result: C;
 	  }
 > {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			MkDialog,
 			{
 				title: props.title,
 				text: props.text,
-				select: {
-					items: props.items,
-					groupedItems: props.groupedItems,
-					default: props.default,
-				},
+				select: props.items
+					? {
+							items: props.items,
+							default: props.default,
+						}
+					: {
+							groupedItems: props.groupedItems,
+							default: props.default,
+						},
 			},
 			{
 				done: (result) => {
-					resolve(result || { canceled: true });
+					if (result.canceled) {
+						resolve({ canceled: true });
+					} else {
+						resolve(result as never);
+					}
 				},
 			},
 			"closed",
@@ -576,7 +611,7 @@ export function select<C = any>(
 }
 
 export function success(): Promise<void> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		const showing = ref(true);
 		window.setTimeout(() => {
 			showing.value = false;
@@ -596,7 +631,7 @@ export function success(): Promise<void> {
 }
 
 export function waiting(): Promise<void> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		const showing = ref(true);
 		popup(
 			MkWaitingDialog,
@@ -612,14 +647,9 @@ export function waiting(): Promise<void> {
 	});
 }
 
-export function form<T extends Record<string, FormItemType>>(
-	title: string,
-	form: T,
-) {
+export function form<T extends Form>(title: string, form: T) {
 	return new Promise<{
-		result?: {
-			[K in keyof T]: GetFormResultType<T[K]["type"]>;
-		};
+		result?: GetFormResultType<T>;
 		canceled?: true;
 	}>((resolve, _reject) => {
 		popup(
@@ -639,8 +669,8 @@ export function form<T extends Record<string, FormItemType>>(
 	});
 }
 
-export async function selectUser() {
-	return new Promise<entities.UserDetailed>((resolve, reject) => {
+export function selectUser() {
+	return new Promise<entities.UserDetailed>((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkUserSelectDialog.vue"),
@@ -658,8 +688,8 @@ export async function selectUser() {
 	});
 }
 
-export async function selectLocalUser() {
-	return new Promise((resolve, reject) => {
+export function selectLocalUser() {
+	return new Promise<entities.UserDetailed>((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkUserSelectLocalDialog.vue"),
@@ -677,8 +707,8 @@ export async function selectLocalUser() {
 	});
 }
 
-export async function selectInstance(): Promise<entities.Instance> {
-	return new Promise((resolve, reject) => {
+export function selectInstance(): Promise<entities.Instance> {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkInstanceSelectDialog.vue"),
@@ -696,8 +726,10 @@ export async function selectInstance(): Promise<entities.Instance> {
 	});
 }
 
-export async function selectDriveFile(multiple: boolean) {
-	return new Promise((resolve, reject) => {
+export function selectDriveFile<Multiple extends boolean>(multiple: Multiple) {
+	return new Promise<
+		Multiple extends true ? entities.DriveFile[] : entities.DriveFile
+	>((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkDriveSelectDialog.vue"),
@@ -711,7 +743,7 @@ export async function selectDriveFile(multiple: boolean) {
 			{
 				done: (files) => {
 					if (files) {
-						resolve(multiple ? files : files[0]);
+						resolve((multiple ? files : files[0]) as never);
 					}
 				},
 			},
@@ -721,7 +753,7 @@ export async function selectDriveFile(multiple: boolean) {
 }
 
 export async function selectDriveFolder(multiple: boolean) {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkDriveSelectDialog.vue"),
@@ -745,7 +777,7 @@ export async function selectDriveFolder(multiple: boolean) {
 }
 
 export async function pickEmoji(src: HTMLElement | null, opts) {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkEmojiPickerDialog.vue"),
@@ -772,7 +804,7 @@ export async function cropImage(
 		aspectRatio: number;
 	},
 ): Promise<entities.DriveFile> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkCropperDialog.vue"),
@@ -795,13 +827,13 @@ export async function cropImage(
 
 type AwaitType<T> = T extends Promise<infer U>
 	? U
-	: T extends (...args: any[]) => Promise<infer V>
+	: T extends (...args: unknown[]) => Promise<infer V>
 		? V
 		: T;
 let openingEmojiPicker: AwaitType<ReturnType<typeof popup>> | null = null;
-let activeTextarea: HTMLTextAreaElement | HTMLInputElement | null = null;
+let activeTextarea: HTMLTextAreaElement | HTMLInputElement;
 export async function openEmojiPicker(
-	src?: HTMLElement,
+	src: HTMLElement | undefined,
 	opts,
 	initialTextarea: typeof activeTextarea,
 ) {
@@ -809,7 +841,7 @@ export async function openEmojiPicker(
 
 	activeTextarea = initialTextarea;
 
-	const textareas = document.querySelectorAll("textarea, input");
+	const textareas = document.querySelectorAll<HTMLTextAreaElement | HTMLInputElement>("textarea, input");
 	for (const textarea of Array.from(textareas)) {
 		textarea.addEventListener("focus", () => {
 			activeTextarea = textarea;
@@ -821,7 +853,7 @@ export async function openEmojiPicker(
 			for (const node of Array.from(record.addedNodes).filter(
 				(node) => node instanceof HTMLElement,
 			) as HTMLElement[]) {
-				const textareas = node.querySelectorAll("textarea, input");
+				const textareas = node.querySelectorAll<HTMLTextAreaElement | HTMLInputElement>("textarea, input");
 				for (const textarea of Array.from(textareas).filter(
 					(textarea) => textarea.dataset.preventEmojiInsert == null,
 				)) {
@@ -859,7 +891,7 @@ export async function openEmojiPicker(
 				insertTextAtCursor(activeTextarea, emoji);
 			},
 			closed: () => {
-				openingEmojiPicker!.dispose();
+				openingEmojiPicker?.dispose();
 				openingEmojiPicker = null;
 				observer.disconnect();
 			},
@@ -910,8 +942,8 @@ export function contextMenu(
 	ev: MouseEvent,
 ) {
 	ev.preventDefault();
-	return new Promise((resolve, reject) => {
-		let dispose;
+	return new Promise<void>((resolve, _reject) => {
+		let dispose: () => void;
 		popup(
 			defineAsyncComponent({
 				loader: () => import("@/components/MkContextMenu.vue"),
@@ -938,7 +970,7 @@ export function post(
 	props: InstanceType<typeof MkPostFormDialog>["$props"] = {},
 	onClosed?: () => void,
 ) {
-	return new Promise<void>((resolve, reject) => {
+	return new Promise<void>((resolve, _reject) => {
 		// NOTE: MkPostFormDialogをdynamic importするとiOSでテキストエリアに自動フォーカスできない
 		// NOTE: ただ、dynamic importしない場合、MkPostFormDialogインスタンスが使いまわされ、
 		//       Vueが渡されたコンポーネントに内部的に__propsというプロパティを生やす影響で、
@@ -966,7 +998,7 @@ export const deckGlobalEvents = new EventEmitter();
 
 /*
 export function checkExistence(fileData: ArrayBuffer): Promise<any> {
-	return new Promise((resolve, reject) => {
+	return new Promise((resolve, _reject) => {
 		const data = new FormData();
 		data.append('md5', getMD5(fileData));
 
diff --git a/packages/client/src/pages/page-editor/els/page-editor.el.image.vue b/packages/client/src/pages/page-editor/els/page-editor.el.image.vue
index 859f0f1112..3820b140df 100644
--- a/packages/client/src/pages/page-editor/els/page-editor.el.image.vue
+++ b/packages/client/src/pages/page-editor/els/page-editor.el.image.vue
@@ -44,9 +44,9 @@ const props = withDefaults(
 const file = ref<any>(null);
 
 async function choose() {
-	os.selectDriveFile(false).then((fileResponse: any) => {
+	os.selectDriveFile(false).then((fileResponse) => {
 		file.value = fileResponse;
-		props.value.fileId = fileResponse.id;
+		props.value.fileId = fileResponse?.id;
 	});
 }
 
diff --git a/packages/client/src/pages/settings/preferences-backups.vue b/packages/client/src/pages/settings/preferences-backups.vue
index 202de0a082..73e098c4ea 100644
--- a/packages/client/src/pages/settings/preferences-backups.vue
+++ b/packages/client/src/pages/settings/preferences-backups.vue
@@ -299,12 +299,12 @@ function loadFile(): void {
 		});
 
 		// 一応廃棄
-		(window as any).__misskey_input_ref__ = null;
+		window.__misskey_input_ref__ = null;
 	};
 
 	// https://qiita.com/fukasawah/items/b9dc732d95d99551013d
 	// iOS Safari で正常に動かす為のおまじない
-	(window as any).__misskey_input_ref__ = input;
+	window.__misskey_input_ref__ = input;
 
 	input.click();
 }
diff --git a/packages/client/src/pages/user-list-timeline.vue b/packages/client/src/pages/user-list-timeline.vue
index 69f17c1047..5543f768c9 100644
--- a/packages/client/src/pages/user-list-timeline.vue
+++ b/packages/client/src/pages/user-list-timeline.vue
@@ -56,8 +56,8 @@ async function timetravel() {
 		title: i18n.ts.date,
 	});
 	if (canceled) return;
-
-	tlEl.value.timetravel(date);
+	// FIXME:
+	tlEl.value!.timetravel(date);
 }
 
 const headerActions = computed(() =>
diff --git a/packages/client/src/scripts/form.ts b/packages/client/src/scripts/form.ts
index 2cd0ca01dc..dfc1c646dc 100644
--- a/packages/client/src/scripts/form.ts
+++ b/packages/client/src/scripts/form.ts
@@ -1,72 +1,11 @@
-export type FormItem =
-	| {
-			label?: string;
-			type: "string";
-			default: string | null;
-			hidden?: boolean;
-			multiline?: boolean;
-	  }
-	| {
-			label?: string;
-			type: "number";
-			default: number | null;
-			hidden?: boolean;
-			step?: number;
-	  }
-	| {
-			label?: string;
-			type: "boolean";
-			default: boolean | null;
-			hidden?: boolean;
-	  }
-	| {
-			label?: string;
-			type: "enum";
-			default: string | null;
-			hidden?: boolean;
-			enum: string[];
-	  }
-	| {
-			label?: string;
-			type: "radio";
-			default: unknown | null;
-			hidden?: boolean;
-			options: {
-				label: string;
-				value: unknown;
-			}[];
-	  }
-	| {
-			label?: string;
-			type: "object";
-			default: Record<string, unknown> | null;
-			hidden: true;
-	  }
-	| {
-			label?: string;
-			type: "array";
-			default: unknown[] | null;
-			hidden: true;
-	  };
+// TODO: replace this file with @/types/form.ts
+
+import type { FormItemType, GetFormItemResultType } from "@/types/form";
+
+export type FormItem = FormItemType;
 
 export type Form = Record<string, FormItem>;
 
-type GetItemType<Item extends FormItem> = Item["type"] extends "string"
-	? string
-	: Item["type"] extends "number"
-		? number
-		: Item["type"] extends "boolean"
-			? boolean
-			: Item["type"] extends "radio"
-				? unknown
-				: Item["type"] extends "enum"
-					? string
-					: Item["type"] extends "array"
-						? unknown[]
-						: Item["type"] extends "object"
-							? Record<string, unknown>
-							: never;
-
 export type GetFormResultType<F extends Form> = {
-	[P in keyof F]: GetItemType<F[P]>;
+	[P in keyof F]: NonNullable<GetFormItemResultType<F[P]["type"]>>;
 };
diff --git a/packages/client/src/scripts/get-note-menu.ts b/packages/client/src/scripts/get-note-menu.ts
index 873b32d7d7..25091f2da2 100644
--- a/packages/client/src/scripts/get-note-menu.ts
+++ b/packages/client/src/scripts/get-note-menu.ts
@@ -14,6 +14,7 @@ import icon from "@/scripts/icon";
 import { useRouter } from "@/router";
 import { notePage } from "@/filters/note";
 import type { NoteTranslation } from "@/types/note";
+import type { MenuItem } from "@/types/menu";
 
 const router = useRouter();
 
@@ -291,7 +292,7 @@ export function getNoteMenu(props: {
 		props.translating.value = false;
 	}
 
-	let menu;
+	let menu: MenuItem[];
 	if (isSignedIn) {
 		const statePromise = os.api("notes/state", {
 			noteId: appearNote.id,
@@ -396,7 +397,7 @@ export function getNoteMenu(props: {
 					}
 				: undefined,
 			{
-				type: "parent",
+				type: "parent" as const,
 				icon: `${icon("ph-share-network")}`,
 				text: i18n.ts.share,
 				children: [
@@ -499,7 +500,7 @@ export function getNoteMenu(props: {
 			!isAppearAuthor ? null : undefined,
 			!isAppearAuthor
 				? {
-						type: "parent",
+						type: "parent" as const,
 						icon: `${icon("ph-user")}`,
 						text: i18n.ts.user,
 						children: getUserMenu(appearNote.user),
diff --git a/packages/client/src/scripts/select-file.ts b/packages/client/src/scripts/select-file.ts
index adf9f0956a..6b51e5fef9 100644
--- a/packages/client/src/scripts/select-file.ts
+++ b/packages/client/src/scripts/select-file.ts
@@ -9,12 +9,14 @@ import icon from "@/scripts/icon";
 
 const stream = useStream();
 
-function select(
-	src: any,
+function select<Multiple extends boolean>(
+	src: HTMLElement | null | undefined,
 	label: string | null,
-	multiple: boolean,
-): Promise<entities.DriveFile | entities.DriveFile[]> {
-	return new Promise((res, rej) => {
+	multiple: Multiple,
+) {
+	return new Promise<
+		Multiple extends true ? entities.DriveFile[] : entities.DriveFile
+	>((res, rej) => {
 		const keepOriginal = ref(defaultStore.state.keepOriginalUploading);
 
 		const chooseFileFromPc = () => {
@@ -22,6 +24,9 @@ function select(
 			input.type = "file";
 			input.multiple = multiple;
 			input.onchange = () => {
+				if (input.files === null) {
+					return;
+				}
 				const promises = Array.from(input.files).map((file) =>
 					uploadFile(
 						file,
@@ -33,19 +38,19 @@ function select(
 
 				Promise.all(promises)
 					.then((driveFiles) => {
-						res(multiple ? driveFiles : driveFiles[0]);
+						res((multiple ? driveFiles : driveFiles[0]) as never);
 					})
 					.catch((err) => {
 						// アップロードのエラーは uploadFile 内でハンドリングされているためアラートダイアログを出したりはしてはいけない
 					});
 
 				// 一応廃棄
-				(window as any).__misskey_input_ref__ = null;
+				window.__misskey_input_ref__ = null;
 			};
 
 			// https://qiita.com/fukasawah/items/b9dc732d95d99551013d
 			// iOS Safari で正常に動かす為のおまじない
-			(window as any).__misskey_input_ref__ = input;
+			window.__misskey_input_ref__ = input;
 
 			input.click();
 		};
@@ -69,7 +74,7 @@ function select(
 				const connection = stream.useChannel("main");
 				connection.on("urlUploadFinished", (urlResponse) => {
 					if (urlResponse.marker === marker) {
-						res(multiple ? [urlResponse.file] : urlResponse.file);
+						res((multiple ? [urlResponse.file] : urlResponse.file) as never);
 						connection.dispose();
 					}
 				});
@@ -122,15 +127,15 @@ function select(
 }
 
 export function selectFile(
-	src: any,
+	src: HTMLElement | null | undefined,
 	label: string | null = null,
-): Promise<entities.DriveFile> {
-	return select(src, label, false) as Promise<entities.DriveFile>;
+) {
+	return select(src, label, false);
 }
 
 export function selectFiles(
-	src: any,
+	src: HTMLElement | null | undefined,
 	label: string | null = null,
-): Promise<entities.DriveFile[]> {
-	return select(src, label, true) as Promise<entities.DriveFile[]>;
+) {
+	return select(src, label, true);
 }
diff --git a/packages/client/src/types/form.ts b/packages/client/src/types/form.ts
index 9c34df30dc..88f90ebbef 100644
--- a/packages/client/src/types/form.ts
+++ b/packages/client/src/types/form.ts
@@ -54,18 +54,18 @@ export type FormItemSwitch = BaseFormItem & {
 };
 export type FormItemSelect = BaseFormItem & {
 	type: "enum";
-	default?: string | null;
+	default?: string | number | symbol | null;
 	enum: {
-		value: string | number | symbol | undefined;
+		value: string | number | symbol;
 		label: string;
 	}[];
 };
 export type FormItemRadios = BaseFormItem & {
 	type: "radio";
-	default?: string | number | symbol | undefined | null;
+	default?: string | number | symbol | null;
 	options: {
 		label: string;
-		value: string | number | symbol | undefined;
+		value: string | number | symbol;
 	}[];
 };
 export type FormItemRange = BaseFormItem & {
@@ -114,10 +114,25 @@ export type FormItemInput = FormItemInputArray[number];
 
 export type FormItemType = FormItemTypeArray[number];
 
-export type GetFormItemByType<T extends FormItemType["type"], F extends FormItemType = FormItemType> = F extends {type: T} ? F : never;
+export type Form = Record<string, FormItemType>;
+
+export type GetFormItemByType<
+	T extends FormItemType["type"],
+	F extends FormItemType = FormItemType,
+> = F extends { type: T } ? F : never;
 
 type NonUndefindAble<T> = T extends undefined ? never : T;
+type NonNullAble<T> = T extends null ? never : T;
 
-export type GetFormResultType<T extends FormItemType["type"], I extends FormItemType = GetFormItemByType<T>> = NonUndefindAble<
+export type GetFormItemResultType<
+	T extends FormItemType["type"],
+	I extends FormItemType = GetFormItemByType<T>,
+> = NonUndefindAble<
 	"__result_typedef" extends keyof I ? I["__result_typedef"] : I["default"]
->
+>;
+
+export type GetFormResultType<F extends Form> = {
+	[K in keyof F]: F[K]["required"] extends false
+		? GetFormItemResultType<F[K]["type"]>
+		: NonNullAble<GetFormItemResultType<F[K]["type"]>>;
+};
diff --git a/packages/client/src/widgets/widget.ts b/packages/client/src/widgets/widget.ts
index 9f33cecfa2..1fdcca86f1 100644
--- a/packages/client/src/widgets/widget.ts
+++ b/packages/client/src/widgets/widget.ts
@@ -23,9 +23,7 @@ export interface WidgetComponentExpose {
 	configure: () => void;
 }
 
-export const useWidgetPropsManager = <
-	F extends Form & Record<string, { default: any }>,
->(
+export const useWidgetPropsManager = <F extends Form>(
 	name: string,
 	propsDef: F,
 	props: Readonly<WidgetComponentProps<GetFormResultType<F>>>,
diff --git a/packages/firefish-js/src/api.ts b/packages/firefish-js/src/api.ts
index 2639712a3f..4a7e1f0b64 100644
--- a/packages/firefish-js/src/api.ts
+++ b/packages/firefish-js/src/api.ts
@@ -122,6 +122,6 @@ export class APIClient {
 				.catch(reject);
 		});
 
-		return promise as any;
+		return promise;
 	}
 }
diff --git a/packages/firefish-js/src/api.types.ts b/packages/firefish-js/src/api.types.ts
index 30ae1f9cdf..c0a7c9019b 100644
--- a/packages/firefish-js/src/api.types.ts
+++ b/packages/firefish-js/src/api.types.ts
@@ -36,6 +36,7 @@ import type {
 	UserDetailed,
 	UserGroup,
 	UserList,
+	UserLite,
 	UserSorting,
 } from "./entities";