#385

AGENTS.md

@@ -106,10 +106,6 @@ npm run preview
 - Explain risks directly.
 - Prefer single quotes for strings unless interpolation or escaping makes
   double quotes better.
-- For Japanese text, follow the 1986 Cabinet Notice
-  《現代仮名遣い》 as the default orthography.
-- For Japanese kanji spelling, do not apply
-  《当用漢字による書きかえ》; prefer the original spelling as the formal one.
 - Ruby: never put a space before method-call parentheses.
 - Ruby: `render` 系メソッド呼び出しでは、keyword 引数付きでも括弧を書かない。
 - Ruby: never put a line break immediately before `)`.
@@ -259,11 +255,8 @@ const value =
   `!==` over negating a comparison like `!(a === b)`.
 - In TypeScript and TSX, prefer `++i` or `--i` over `i += 1` or `i -= 1` for
   simple unit-step counter updates.
-- For user-facing Japanese text, follow the 1986 Cabinet Notice
+- For user-facing Japanese text, prefer modern kana usage and natural current
-  《現代仮名遣い》 and avoid historical kana spellings unless the task
+  phrasing over historical spellings or awkward literal wording.
-  explicitly requires them.
-- For user-facing Japanese kanji spelling, do not normalize to
-  《当用漢字による書きかえ》; prefer original forms such as `編輯`.
 - For user-facing Japanese ellipses, prefer `……` over ASCII `...`.
 
 ### Frontend TSX style

backend/app/controllers/user_settings_controller.rb

@@ -1,61 +0,0 @@
-class UserSettingsController < ApplicationController
-  wrap_parameters false
-
-  def show
-    return head :unauthorized unless current_user
-
-    render json: current_setting.serializable_hash
-  end
-
-  def update
-    return head :unauthorized unless current_user
-
-    raw_attributes = editable_raw_attributes
-    field_errors = validate_raw_attributes(raw_attributes)
-    return render_validation_error fields: field_errors if field_errors.present?
-
-    setting = current_setting
-    setting.assign_attributes(raw_attributes)
-
-    if setting.save
-      render json: setting.serializable_hash, status: :ok
-    else
-      render_validation_error setting
-    end
-  end
-
-  private
-
-  def current_setting
-    Setting.find_or_create_by!(user: current_user) do |setting|
-      setting.assign_attributes(Setting.defaults)
-    end
-  rescue ActiveRecord::RecordNotUnique
-    Setting.find_by!(user: current_user)
-  end
-
-  def editable_raw_attributes
-    request.request_parameters.slice(*Setting::EDITABLE_ATTRIBUTES)
-  end
-
-  def validate_raw_attributes raw_attributes
-    raw_attributes.each_with_object({ }) do |(key, value), errors|
-      next if value_matches_type?(key, value)
-
-      errors[key.to_sym] = ['値の型が不正です．']
-    end
-  end
-
-  def value_matches_type? key, value
-    case Setting::TYPE_BY_ATTRIBUTE.fetch(key)
-    when :string
-      value.is_a?(String)
-    when :integer
-      value.is_a?(Integer)
-    when :boolean
-      value == true || value == false
-    else
-      false
-    end
-  end
-end

backend/app/models/setting.rb

@@ -1,49 +1,7 @@
 class Setting < ApplicationRecord
-  THEMES = ['system', 'light', 'dark'].freeze
-  AUTO_FETCH_MODES = ['auto', 'manual', 'off'].freeze
-  WIKI_EDITOR_MODES = ['split', 'write', 'preview'].freeze
-
-  STRING_ATTRIBUTES = [
-    'theme',
-    'auto_fetch_title',
-    'auto_fetch_thumbnail',
-    'wiki_editor_mode',
-  ].freeze
-  INTEGER_ATTRIBUTES = [].freeze
-  BOOLEAN_ATTRIBUTES = [].freeze
-  EDITABLE_ATTRIBUTES =
-      (STRING_ATTRIBUTES + INTEGER_ATTRIBUTES + BOOLEAN_ATTRIBUTES).freeze
-  TYPE_BY_ATTRIBUTE = {
-    'theme' => :string,
-    'auto_fetch_title' => :string,
-    'auto_fetch_thumbnail' => :string,
-    'wiki_editor_mode' => :string,
-  }.freeze
-
   belongs_to :user
 
   validates :user_id, presence: true
-  validates :user_id, uniqueness: true
+  validates :key, presence: true, length: { maximum: 255 }
-
+  validates :value, presence: true
-  validates :theme, inclusion: { in: THEMES }
-  validates :auto_fetch_title, inclusion: { in: AUTO_FETCH_MODES }
-  validates :auto_fetch_thumbnail, inclusion: { in: AUTO_FETCH_MODES }
-  validates :wiki_editor_mode, inclusion: { in: WIKI_EDITOR_MODES }
-
-  def self.defaults
-    {
-      theme: 'system',
-      auto_fetch_title: 'manual',
-      auto_fetch_thumbnail: 'manual',
-      wiki_editor_mode: 'split',
-    }
-  end
-
-  def self.serializable_attributes
-    EDITABLE_ATTRIBUTES.map(&:to_sym)
-  end
-
-  def serializable_hash(options = nil)
-    super({ only: self.class.serializable_attributes }.merge(options || { }))
-  end
 end

backend/app/models/user.rb

@@ -7,7 +7,7 @@ class User < ApplicationRecord
 
   has_many :created_posts,
            class_name: 'Post', foreign_key: :uploaded_user_id, dependent: :nullify
-  has_one :setting, dependent: :destroy
+  has_many :settings
   has_many :user_ips, dependent: :destroy
   has_many :ip_addresses, through: :user_ips
   has_many :user_post_views, dependent: :destroy

backend/config/routes.rb

@@ -81,9 +81,6 @@ Rails.application.routes.draw do
     end
   end
 
-  get 'users/settings', to: 'user_settings#show'
-  patch 'users/settings', to: 'user_settings#update'
-
   resources :users, only: [:create, :update] do
     collection do
       post :verify

backend/db/migrate/20260704000000_rebuild_settings_as_typed_user_settings.rb

@@ -1,31 +0,0 @@
-class RebuildSettingsAsTypedUserSettings < ActiveRecord::Migration[8.0]
-  def change
-    remove_foreign_key :settings, :users if foreign_key_exists?(:settings, :users)
-    remove_index :settings, :user_id if index_exists?(:settings, :user_id)
-
-    remove_column :settings, :key, :string if column_exists?(:settings, :key)
-    remove_column :settings, :value, :json if column_exists?(:settings, :value)
-
-    change_column_null :settings, :user_id, false
-
-    add_column :settings, :theme, :string, null: false, default: 'system'
-    add_column :settings,
-               :auto_fetch_title,
-               :string,
-               null: false,
-               default: 'manual'
-    add_column :settings,
-               :auto_fetch_thumbnail,
-               :string,
-               null: false,
-               default: 'manual'
-    add_column :settings,
-               :wiki_editor_mode,
-               :string,
-               null: false,
-               default: 'split'
-
-    add_index :settings, :user_id, unique: true
-    add_foreign_key :settings, :users
-  end
-end

backend/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.0].define(version: 2026_07_04_000000) do
+ActiveRecord::Schema[8.0].define(version: 2026_06_26_010000) do
   create_table "active_storage_attachments", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "name", null: false
     t.string "record_type", null: false
@@ -374,13 +374,11 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_04_000000) do
 
   create_table "settings", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "user_id", null: false
+    t.string "key", null: false
+    t.json "value", null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.string "theme", default: "system", null: false
+    t.index ["user_id"], name: "index_settings_on_user_id"
-    t.string "auto_fetch_title", default: "manual", null: false
-    t.string "auto_fetch_thumbnail", default: "manual", null: false
-    t.string "wiki_editor_mode", default: "split", null: false
-    t.index ["user_id"], name: "index_settings_on_user_id", unique: true
   end
 
   create_table "tag_implications", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|

frontend/src/App.tsx

@@ -10,7 +10,6 @@ import DevModeWatermark from '@/components/DevModeWatermark'
 import RouteBlockerOverlay from '@/components/RouteBlockerOverlay'
 import TopNav from '@/components/TopNav'
 import DialogueProvider from '@/components/dialogues/DialogueProvider'
-import { UserSettingsProvider } from '@/components/users/UserSettingsProvider'
 import { Toaster } from '@/components/ui/toaster'
 import { apiPost, isApiError } from '@/lib/api'
 import DeerjikistDetailPage from '@/pages/deerjikists/DeerjikistDetailPage'
@@ -146,26 +145,24 @@ const App: FC = () => {
 
   return (
       <>
-	<UserSettingsProvider user={user}>
+	<RouteBlockerOverlay/>
-	  <RouteBlockerOverlay/>
+	{import.meta.env.DEV && <DevModeWatermark/>}
-	  {import.meta.env.DEV && <DevModeWatermark/>}
 
-	  <BrowserRouter>
+	<BrowserRouter>
-	    <DialogueProvider>
+	  <DialogueProvider>
-	      <LayoutGroup>
+	    <LayoutGroup>
-		<motion.div
+	      <motion.div
-		    layout="position"
+		  layout="position"
-		    transition={{ layout: { duration: .2, ease: 'easeOut' } }}
+		  transition={{ layout: { duration: .2, ease: 'easeOut' } }}
-		    className="relative flex flex-col h-dvh w-full overflow-y-hidden">
+		  className="relative flex flex-col h-dvh w-full overflow-y-hidden">
-		  <TopNav user={user}/>
+		<TopNav user={user}/>
-		  <RouteTransitionWrapper user={user} setUser={setUser}/>
+		<RouteTransitionWrapper user={user} setUser={setUser}/>
-		</motion.div>
+	      </motion.div>
-	      </LayoutGroup>
+	    </LayoutGroup>
 
-	      <Toaster/>
+	    <Toaster/>
-	    </DialogueProvider>
+	  </DialogueProvider>
-	  </BrowserRouter>
+	</BrowserRouter>
-	</UserSettingsProvider>
       </>)
 }
 

frontend/src/components/MaterialSidebar.tsx

@@ -488,25 +488,23 @@ const MaterialSidebar: FC = () => {
 	  </div>
 	</div>
 
-	<div className="hidden md:block">
+	<SidebarComponent sidebarKey="materials" className="hidden md:block">
-	  <SidebarComponent>
+	  <div className="space-y-4">
-	    <div className="space-y-4">
+	    <MaterialFilterButtons
-	      <MaterialFilterButtons
+		materialFilter={materialFilter}
-		  materialFilter={materialFilter}
+		onChange={handleFilterChange}/>
-		  onChange={handleFilterChange}/>
+	    {isLoading && (
-	      {isLoading && (
+		<p className="text-sm text-neutral-500 dark:text-stone-400">読込中……</p>)}
-		  <p className="text-sm text-neutral-500 dark:text-stone-400">読込中……</p>)}
+	    {isError && (
-	      {isError && (
+		<p className="text-sm text-red-600 dark:text-red-300">
-		  <p className="text-sm text-red-600 dark:text-red-300">
+		  タグ一覧の取得に失敗しました．
-		    タグ一覧の取得に失敗しました．
+		</p>)}
-		  </p>)}
+	    {(!isLoading && !isError) && (
-	      {(!isLoading && !isError) && (
+		<ul>
-		  <ul>
+		  {renderDesktopTree (visibleRootTags)}
-		    {renderDesktopTree (visibleRootTags)}
+		</ul>)}
-		  </ul>)}
+	  </div>
-	    </div>
+	</SidebarComponent>
-	  </SidebarComponent>
-	</div>
       </>)
 }
 

frontend/src/components/PostFormTagsArea.tsx

@@ -68,12 +68,9 @@ const PostFormTagsArea: FC<Props> = ({ tags, setTags, errors, ...rest }) => {
 
     setBounds ({ start, end })
 
-    const data = await apiGet<Tag[]> ('/tags/autocomplete', { params: {
+    const data = await apiGet<Tag[]> ('/tags/autocomplete', { params: { q: token, nico: '0' } })
-	q: token,
+    setSuggestions (data.filter (t => t.postCount > 0))
-	nico: '0' } })
+    setSuggestionsVsbl (suggestions.length > 0)
-    const nextSuggestions = data.filter (t => t.postCount > 0)
-    setSuggestions (nextSuggestions)
-    setSuggestionsVsbl (nextSuggestions.length > 0)
   }
 
   return (

frontend/src/components/PostList.tsx

@@ -72,4 +72,4 @@ const PostList: FC<Props> = ({ posts, onClick }) => {
       </div>)
 }
 
-export default PostList
+export default PostList

frontend/src/components/TagDetailSidebar.tsx

@@ -146,10 +146,13 @@ const DropSlot = ({ cat }: { cat: Category }) => {
 }
 
 
-type Props = { post: Post; sp?: boolean }
+type Props = {
+    className?: string
+    post:       Post
+    sp?:        boolean }
 
 
-const TagDetailSidebar: FC<Props> = ({ post, sp }) => {
+const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
   sp = Boolean (sp)
 
   const qc = useQueryClient ()
@@ -278,7 +281,7 @@ const TagDetailSidebar: FC<Props> = ({ post, sp }) => {
   }, [baseTags])
 
   return (
-      <SidebarComponent>
+      <SidebarComponent sidebarKey="post-detail-tags" className={className}>
 	<TagSearch/>
 	<DndContext
 	    sensors={sensors}

frontend/src/components/TagSidebar.tsx

@@ -96,7 +96,7 @@ const TagSidebar: FC<Props> = ({ posts, onClick }) => {
       </>)
 
   return (
-      <SidebarComponent>
+      <SidebarComponent sidebarKey="posts-index-tags">
 	<TagSearch/>
 
 	<div className="hidden md:block mt-4">

frontend/src/components/common/TagInput.test.tsx

@@ -26,7 +26,7 @@ describe ('TagInput', () => {
     await waitFor (() => {
       expect (api.apiGet).toHaveBeenCalledWith (
           '/tags/autocomplete',
-          { params: { q: '虹夏', nico: '0' } },
+          { params: { q: '虹夏' } },
       )
     })
     expect (setValue).toHaveBeenCalledWith ('ぼっち 虹夏')
@@ -41,20 +41,4 @@ describe ('TagInput', () => {
     expect (api.apiGet).not.toHaveBeenCalled ()
     expect (setValue).toHaveBeenCalledWith (' ')
   })
-
-  it ('sends nico=1 only when includeNico is true', async () => {
-    const setValue = vi.fn ()
-    api.apiGet.mockResolvedValueOnce ([buildTag ({ name: '虹夏', postCount: 2 })])
-
-    render (<TagInput value="" setValue={setValue} includeNico={true}/>)
-
-    fireEvent.change (screen.getByRole ('textbox'), { target: { value: '虹夏' } })
-
-    await waitFor (() => {
-      expect (api.apiGet).toHaveBeenCalledWith (
-          '/tags/autocomplete',
-          { params: { q: '虹夏', nico: '1' } },
-      )
-    })
-  })
 })

frontend/src/components/common/TagInput.tsx

@@ -10,20 +10,13 @@ import type { Tag } from '@/types'
 
 
 type Props = {
-    includeNico?:   boolean
     describedBy?:  string
     invalid?:      boolean
     value:         string
     setValue:      (value: string) => void }
 
 
-const TagInput: FC<Props> = ({
+const TagInput: FC<Props> = ({ describedBy, invalid, value, setValue }) => {
-    includeNico = false,
-    describedBy,
-    invalid,
-    value,
-    setValue,
-}) => {
   const [activeIndex, setActiveIndex] = useState (-1)
   const [suggestions, setSuggestions] = useState<Tag[]> ([])
   const [suggestionsVsbl, setSuggestionsVsbl] = useState (false)
@@ -39,12 +32,10 @@ const TagInput: FC<Props> = ({
 	return
       }
 
-    const data = await apiGet<Tag[]> ('/tags/autocomplete', { params: {
+    const data = await apiGet<Tag[]> ('/tags/autocomplete', { params: { q } })
-	q,
+    setSuggestions (data.filter (t => t.postCount > 0))
-	nico: includeNico ? '1' : '0' } })
+    if (suggestions.length > 0)
-    const nextSuggestions = data.filter (t => t.postCount > 0)
+      setSuggestionsVsbl (true)
-    setSuggestions (nextSuggestions)
-    setSuggestionsVsbl (nextSuggestions.length > 0)
   }
 
   // TODO: TagSearch からのコピペのため，共通化を考へる．

frontend/src/components/layout/SidebarComponent.test.tsx

@@ -0,0 +1,124 @@
+import { fireEvent, render, screen, waitFor } from '@testing-library/react'
+import { HelmetProvider } from 'react-helmet-async'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import SidebarComponent from '@/components/layout/SidebarComponent'
+
+
+const sidebarWidth = (element: Element | null): string =>
+    (element as HTMLElement).style.getPropertyValue ('--sidebar-width')
+
+
+const sidebarRoot = (container: HTMLElement): Element =>
+    container.querySelector ('[style*="--sidebar-width"]')!
+
+
+const sidebarTree = (props: Partial<Parameters<typeof SidebarComponent>[0]>) => (
+    <HelmetProvider>
+      <div data-sidebar-container>
+	<SidebarComponent sidebarKey="test-sidebar" {...props}>
+	  Sidebar body
+	</SidebarComponent>
+      </div>
+    </HelmetProvider>)
+
+
+const renderSidebar = (
+    props: Partial<Parameters<typeof SidebarComponent>[0]> = {},
+    containerWidth = 800,
+) => {
+  Object.defineProperty (HTMLElement.prototype, 'clientWidth', {
+      configurable: true,
+      get () {
+	return this.hasAttribute ('data-sidebar-container') ? containerWidth : 0
+      },
+  })
+
+  const rendered = render (sidebarTree (props))
+
+  return rendered
+}
+
+
+describe ('SidebarComponent', () => {
+  beforeEach (() => {
+    Object.defineProperty (window, 'innerWidth', {
+	configurable: true,
+	value:        1_000,
+    })
+
+    Object.defineProperty (HTMLElement.prototype, 'setPointerCapture', {
+	configurable: true,
+	value:        vi.fn (),
+    })
+    Object.defineProperty (HTMLElement.prototype, 'releasePointerCapture', {
+	configurable: true,
+	value:        vi.fn (),
+    })
+    Object.defineProperty (HTMLElement.prototype, 'hasPointerCapture', {
+	configurable: true,
+	value:        vi.fn (() => true),
+    })
+
+    vi.spyOn (HTMLElement.prototype, 'setPointerCapture').mockImplementation (() => {
+      ;
+    })
+    vi.spyOn (HTMLElement.prototype, 'releasePointerCapture').mockImplementation (() => {
+      ;
+    })
+    vi.spyOn (HTMLElement.prototype, 'hasPointerCapture').mockReturnValue (true)
+  })
+
+  it ('uses maxWidth without applying the container main-width reserve twice', async () => {
+    localStorage.setItem ('sidebar:test-sidebar:left:width', '700')
+    const onWidthChange = vi.fn ()
+
+    const { container } = renderSidebar ({ maxWidth: 700, onWidthChange }, 800)
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('700px')
+    })
+    expect (onWidthChange).toHaveBeenLastCalledWith (700)
+  })
+
+  it ('resets width and removes only its storage key on double click', async () => {
+    localStorage.setItem ('sidebar:test-sidebar:right:width', '420')
+    localStorage.setItem ('sidebar:other-sidebar:right:width', '480')
+
+    const { container } = renderSidebar ({ side: 'right' }, 900)
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('420px')
+    })
+
+    fireEvent.doubleClick (screen.getByRole ('separator', { name: 'サイドバー幅' }))
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('256px')
+    })
+    expect (localStorage.getItem ('sidebar:test-sidebar:right:width')).toBeNull ()
+    expect (localStorage.getItem ('sidebar:other-sidebar:right:width')).toBe ('480')
+  })
+
+  it ('clamps current width on maxWidth changes without re-reading storage', async () => {
+    localStorage.setItem ('sidebar:test-sidebar:left:width', '420')
+
+    const { container, rerender } = renderSidebar ({ maxWidth: 420 }, 900)
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('420px')
+    })
+
+    rerender (sidebarTree ({ maxWidth: 300 }))
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('300px')
+    })
+
+    rerender (sidebarTree ({ maxWidth: 500 }))
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('300px')
+    })
+  })
+})

frontend/src/components/layout/SidebarComponent.tsx

@@ -1,19 +1,319 @@
 import { motion } from 'framer-motion'
 import { Helmet } from 'react-helmet-async'
 
-import type { FC, ReactNode } from 'react'
+import { cn } from '@/lib/utils'
 
-type Props = { children: ReactNode }
+import type { CSSProperties, FC, MouseEvent, PointerEvent, ReactNode } from 'react'
+import { useCallback, useEffect, useRef, useState } from 'react'
+
+type SidebarSide = 'left' | 'right'
+
+type Props = {
+    children:      ReactNode
+    className?:    string
+    maxWidth?:     number
+    onWidthChange?: (width: number) => void
+    sidebarKey:    string
+    side?:         SidebarSide }
+
+type ResizeState = {
+    pointerId:  number
+    startWidth: number
+    startX:     number
+    side:       SidebarSide }
+
+type PendingPressState = ResizeState & { startY: number }
+
+const DEFAULT_SIDEBAR_WIDTH = 256
+const MIN_SIDEBAR_WIDTH = 192
+const MIN_MAIN_WIDTH = 360
+const MAX_VIEWPORT_WIDTH_RATIO = .8
+const LONG_PRESS_DELAY_MS = 350
+const TOUCH_MOVE_THRESHOLD_PX = 8
 
 
-const SidebarComponent: FC<Props> = ({ children }) => (
+const storageKeyForSidebar = (sidebarKey: string, side: SidebarSide): string =>
-    <motion.div
+    `sidebar:${ sidebarKey }:${ side }:width`
-	layout="position"
+
-	transition={{ layout: { duration: .2, ease: 'easeOut' } }}
+
-	className="p-4 w-full md:w-64 md:h-full md:overflow-y-auto sidebar">
+const getSidebarMaxWidth = (containerWidth: number): number => {
-      <Helmet>
+  const viewportWidth =
-	<style>
+      typeof window === 'undefined' ? containerWidth : window.innerWidth
-	  {`
+  const viewportMaxWidth = Math.floor (viewportWidth * MAX_VIEWPORT_WIDTH_RATIO)
+  const containerMaxWidth = Math.floor (containerWidth - MIN_MAIN_WIDTH)
+  const dynamicMaxWidth = Math.min (viewportMaxWidth, containerMaxWidth)
+
+  return Math.max (MIN_SIDEBAR_WIDTH, dynamicMaxWidth)
+}
+
+
+const readStoredSidebarWidth = (
+    sidebarKey: string,
+    side: SidebarSide): number => {
+  if (typeof window === 'undefined')
+    return DEFAULT_SIDEBAR_WIDTH
+
+  const value = window.localStorage.getItem (storageKeyForSidebar (sidebarKey, side))
+  const width = value == null ? Number.NaN : Number (value)
+
+  return Number.isFinite (width) ? width : DEFAULT_SIDEBAR_WIDTH
+}
+
+
+const SidebarComponent: FC<Props> = ({
+    children,
+    className,
+    maxWidth,
+    onWidthChange,
+    sidebarKey,
+    side = 'left',
+}) => {
+  const rootRef = useRef<HTMLDivElement | null> (null)
+  const maxWidthRef = useRef (maxWidth)
+  const getContainerWidth = useCallback (() => {
+    const containerWidth = rootRef.current
+	?.closest ('[data-sidebar-container]')
+	?.clientWidth
+    ?? window.innerWidth
+    return containerWidth
+  }, [])
+  const getClampedWidth = useCallback ((
+      nextWidth: number,
+      containerWidth: number): number => {
+    const viewportWidth =
+	typeof window === 'undefined' ? containerWidth : window.innerWidth
+    const viewportMaxWidth = Math.floor (viewportWidth * MAX_VIEWPORT_WIDTH_RATIO)
+    const maxAllowedWidth =
+	maxWidthRef.current == null
+	? getSidebarMaxWidth (containerWidth)
+	: Math.max (
+	    MIN_SIDEBAR_WIDTH,
+	    Math.min (viewportMaxWidth, maxWidthRef.current))
+
+    return Math.min (maxAllowedWidth, Math.max (MIN_SIDEBAR_WIDTH, nextWidth))
+  }, [])
+
+  const [width, setWidth] = useState (() => (
+      typeof window === 'undefined'
+      ? DEFAULT_SIDEBAR_WIDTH
+      : getClampedWidth (
+	  readStoredSidebarWidth (sidebarKey, side),
+	  window.innerWidth)))
+  const [resizing, setResizing] = useState (false)
+  const widthRef = useRef (width)
+  const longPressTimerRef = useRef<ReturnType<typeof setTimeout> | null> (null)
+  const pendingPressRef = useRef<PendingPressState | null> (null)
+  const resizeRef = useRef<ResizeState | null> (null)
+  const bodyStyleRef = useRef<{ cursor: string, userSelect: string } | null> (null)
+
+  const clearLongPressTimer = useCallback (() => {
+    if (longPressTimerRef.current == null)
+      return
+
+    clearTimeout (longPressTimerRef.current)
+    longPressTimerRef.current = null
+  }, [])
+
+  const restoreBodyStyle = useCallback (() => {
+    if (bodyStyleRef.current == null)
+      return
+
+    document.body.style.cursor = bodyStyleRef.current.cursor
+    document.body.style.userSelect = bodyStyleRef.current.userSelect
+    bodyStyleRef.current = null
+  }, [])
+
+  const startResize = useCallback ((state: ResizeState) => {
+    clearLongPressTimer ()
+    pendingPressRef.current = null
+    resizeRef.current = state
+    setResizing (true)
+
+    if (bodyStyleRef.current == null)
+    {
+      bodyStyleRef.current = {
+	  cursor: document.body.style.cursor,
+	  userSelect: document.body.style.userSelect }
+    }
+
+    document.body.style.cursor = 'col-resize'
+    document.body.style.userSelect = 'none'
+  }, [clearLongPressTimer])
+
+  const finishResize = useCallback (() => {
+    clearLongPressTimer ()
+    pendingPressRef.current = null
+
+    const state = resizeRef.current
+    resizeRef.current = null
+
+    if (state != null)
+      window.localStorage.setItem (
+	  storageKeyForSidebar (sidebarKey, state.side),
+	  String (widthRef.current))
+
+    setResizing (false)
+    restoreBodyStyle ()
+  }, [clearLongPressTimer, restoreBodyStyle, sidebarKey])
+
+  const applyWidth = useCallback ((nextWidth: number) => {
+    if (nextWidth === widthRef.current)
+      return
+
+    widthRef.current = nextWidth
+    setWidth (nextWidth)
+  }, [])
+
+  useEffect (() => {
+    maxWidthRef.current = maxWidth
+    const containerWidth = getContainerWidth ()
+    const nextWidth = getClampedWidth (widthRef.current, containerWidth)
+    applyWidth (nextWidth)
+  }, [applyWidth, getClampedWidth, getContainerWidth, maxWidth])
+
+  const updateWidth = useCallback ((clientX: number) => {
+    const state = resizeRef.current
+    if (state == null)
+      return
+
+    const containerWidth = getContainerWidth ()
+    const delta = state.side === 'left'
+		  ? clientX - state.startX
+		  : state.startX - clientX
+    const nextWidth = getClampedWidth (state.startWidth + delta, containerWidth)
+    applyWidth (nextWidth)
+  }, [applyWidth, getClampedWidth, getContainerWidth])
+
+  const handlePointerDown = (ev: PointerEvent<HTMLDivElement>) => {
+    if (ev.pointerType !== 'mouse' && ev.pointerType !== 'touch')
+      return
+
+    if (ev.pointerType === 'mouse' && ev.button !== 0)
+      return
+
+    ev.preventDefault ()
+    ev.stopPropagation ()
+    ev.currentTarget.setPointerCapture (ev.pointerId)
+
+    const state = {
+	pointerId: ev.pointerId,
+	side,
+	startWidth: widthRef.current,
+	startX: ev.clientX }
+
+    if (ev.pointerType === 'mouse')
+    {
+      startResize (state)
+      return
+    }
+
+    pendingPressRef.current = { ...state, startY: ev.clientY }
+    clearLongPressTimer ()
+    longPressTimerRef.current = setTimeout (() => {
+      if (pendingPressRef.current != null)
+	startResize (pendingPressRef.current)
+    }, LONG_PRESS_DELAY_MS)
+  }
+
+  const handlePointerMove = (ev: PointerEvent<HTMLDivElement>) => {
+    ev.stopPropagation ()
+
+    if (resizeRef.current != null)
+    {
+      ev.preventDefault ()
+      updateWidth (ev.clientX)
+      return
+    }
+
+    const pendingPress = pendingPressRef.current
+    if (pendingPress == null || pendingPress.pointerId !== ev.pointerId)
+      return
+
+    const deltaX = ev.clientX - pendingPress.startX
+    const deltaY = ev.clientY - pendingPress.startY
+    const distance = Math.hypot (deltaX, deltaY)
+
+    if (distance >= TOUCH_MOVE_THRESHOLD_PX)
+    {
+      clearLongPressTimer ()
+      pendingPressRef.current = null
+    }
+  }
+
+  const handlePointerEnd = (ev: PointerEvent<HTMLDivElement>) => {
+    ev.stopPropagation ()
+
+    if (ev.currentTarget.hasPointerCapture (ev.pointerId))
+      ev.currentTarget.releasePointerCapture (ev.pointerId)
+
+    finishResize ()
+  }
+
+  const resetWidth = useCallback (() => {
+    const containerWidth = getContainerWidth ()
+    const nextWidth = getClampedWidth (DEFAULT_SIDEBAR_WIDTH, containerWidth)
+    applyWidth (nextWidth)
+    window.localStorage.removeItem (storageKeyForSidebar (sidebarKey, side))
+  }, [applyWidth, getClampedWidth, getContainerWidth, sidebarKey, side])
+
+  const handleDoubleClick = (ev: MouseEvent<HTMLDivElement>) => {
+    ev.preventDefault ()
+    ev.stopPropagation ()
+    resetWidth ()
+  }
+
+  useEffect (() => {
+    const containerWidth = getContainerWidth ()
+    const nextWidth = getClampedWidth (
+	readStoredSidebarWidth (sidebarKey, side),
+	containerWidth)
+    applyWidth (nextWidth)
+  }, [applyWidth, getClampedWidth, getContainerWidth, sidebarKey, side])
+
+  useEffect (() => {
+    const containerWidth = getContainerWidth ()
+    const nextWidth = getClampedWidth (widthRef.current, containerWidth)
+    applyWidth (nextWidth)
+  }, [applyWidth, getClampedWidth, getContainerWidth])
+
+  useEffect (() => {
+    if (typeof window === 'undefined')
+      return
+
+    const handleResize = () => {
+      const containerWidth = getContainerWidth ()
+      const nextWidth = getClampedWidth (widthRef.current, containerWidth)
+      applyWidth (nextWidth)
+    }
+
+    window.addEventListener ('resize', handleResize)
+    return () => window.removeEventListener ('resize', handleResize)
+  }, [applyWidth, getClampedWidth, getContainerWidth])
+
+  useEffect (() => {
+    onWidthChange?.(width)
+  }, [onWidthChange, width])
+
+  useEffect (() => () => {
+    clearLongPressTimer ()
+    restoreBodyStyle ()
+  }, [clearLongPressTimer, restoreBodyStyle])
+
+  const style = {
+      '--sidebar-width': `${ width }px` } as CSSProperties
+
+  return (
+      <motion.div
+	  ref={rootRef}
+	  layout="position"
+	  transition={{ layout: { duration: .2, ease: 'easeOut' } }}
+	  style={style}
+	  className={cn (
+	      'relative w-full md:w-[var(--sidebar-width)] md:shrink-0 md:h-full',
+	      className)}>
+	<Helmet>
+	  <style>
+	    {`
 	      .sidebar
 	      {
 		direction: rtl;
@@ -23,10 +323,34 @@ const SidebarComponent: FC<Props> = ({ children }) => (
 	      {
 		direction: ltr;
 	      }`}
-	</style>
+	  </style>
-      </Helmet>
+	</Helmet>
 
-      {children}
+	<div className="h-full overflow-y-auto p-4 sidebar">
-    </motion.div>)
+	  {children}
+	</div>
 
-export default SidebarComponent
+	<div
+	    role="separator"
+	    aria-orientation="vertical"
+	    aria-label="サイドバー幅"
+	    onPointerDown={handlePointerDown}
+	    onPointerMove={handlePointerMove}
+	    onPointerUp={handlePointerEnd}
+	    onPointerCancel={handlePointerEnd}
+	    onDoubleClick={handleDoubleClick}
+	    className={cn (
+		'hidden md:block absolute top-0 bottom-0 z-20 w-4 cursor-col-resize',
+		'touch-none select-none',
+		side === 'left' ? '-right-2' : '-left-2',
+		'before:absolute before:top-0 before:bottom-0 before:w-px',
+		'before:bg-neutral-500/0 hover:before:bg-neutral-500/30',
+		'before:transition-colors before:duration-150',
+		side === 'left'
+		? 'before:left-1/2'
+		: 'before:right-1/2',
+		resizing && 'before:bg-neutral-500/40')}/>
+      </motion.div>)
+}
+
+export default SidebarComponent

frontend/src/components/users/UserSettingsProvider.tsx

@@ -1,113 +0,0 @@
-import { createContext, useContext, useEffect, useMemo, useState } from 'react'
-
-import { DEFAULT_USER_SETTINGS, fetchUserSettings } from '@/lib/settings'
-
-import type { Dispatch, FC, ReactNode, SetStateAction } from 'react'
-
-import type { User } from '@/types'
-import type { UserSettings } from '@/lib/settings'
-
-type ContextValue = {
-    loaded:       boolean
-    error:        string | null
-    settings:     UserSettings
-    setSettings:  Dispatch<SetStateAction<UserSettings>> }
-
-const UserSettingsContext = createContext<ContextValue | null> (null)
-
-
-const applyTheme = (theme: UserSettings['theme']) => {
-  const root = document.documentElement
-  const media = window.matchMedia ('(prefers-color-scheme: dark)')
-
-  const sync = () => {
-    const dark = theme === 'dark' || (theme === 'system' && media.matches)
-    root.classList.toggle ('dark', dark)
-    root.style.colorScheme = dark ? 'dark' : 'light'
-  }
-
-  sync ()
-
-  if (theme !== 'system')
-    return () => { }
-
-  const onChange = () => sync ()
-  media.addEventListener ('change', onChange)
-  return () => {
-    media.removeEventListener ('change', onChange)
-  }
-}
-
-
-export const UserSettingsProvider: FC<{
-    children:  ReactNode
-    user:      User | null }> = ({ children, user }) => {
-  const [error, setError] = useState<string | null> (null)
-  const [loaded, setLoaded] = useState (false)
-  const [settings, setSettings] = useState<UserSettings> (DEFAULT_USER_SETTINGS)
-
-  useEffect (() => {
-    let cancelled = false
-
-    if (!(user))
-      {
-	setError (null)
-	setSettings (DEFAULT_USER_SETTINGS)
-	setLoaded (true)
-	return
-      }
-
-    setLoaded (false)
-    setError (null)
-
-    void (async () => {
-      try
-      {
-	const next = await fetchUserSettings ()
-	if (!(cancelled))
-	  {
-	    setError (null)
-	    setSettings (next)
-	    setLoaded (true)
-	  }
-      }
-      catch
-      {
-	if (!(cancelled))
-	  {
-	    setError ('設定を読み込めませんでした．既定値で表示しています．')
-	    setSettings (DEFAULT_USER_SETTINGS)
-	    setLoaded (true)
-	  }
-      }
-    }) ()
-
-    return () => {
-      cancelled = true
-    }
-  }, [user])
-
-  useEffect (() => applyTheme (settings.theme), [settings.theme])
-
-  const value = useMemo<ContextValue> (() => ({
-      error,
-      loaded,
-      settings,
-      setSettings,
-  }), [error, loaded, settings])
-
-  return (
-      <UserSettingsContext.Provider value={value}>
-	{children}
-      </UserSettingsContext.Provider>)
-}
-
-
-export const useUserSettings = (): ContextValue => {
-  const value = useContext (UserSettingsContext)
-
-  if (value == null)
-    throw new Error ('UserSettingsProvider is missing')
-
-  return value
-}

frontend/src/index.css

@@ -87,29 +87,6 @@
   -moz-osx-font-smoothing: grayscale;
 }
 
-:root[data-font-size='small']
-{
-  font-size: 14px;
-}
-
-:root[data-font-size='normal']
-{
-  font-size: 16px;
-}
-
-:root[data-font-size='large']
-{
-  font-size: 18px;
-}
-
-:root[data-display-density='compact'] input,
-:root[data-display-density='compact'] textarea,
-:root[data-display-density='compact'] select,
-:root[data-display-density='compact'] button
-{
-  line-height: 1.25;
-}
-
 a
 {
   font-weight: 500;

frontend/src/lib/settings.ts

@@ -1,282 +0,0 @@
-import { apiGet, apiPatch } from '@/lib/api'
-
-import type { FetchPostsOrder, FetchTagsOrder } from '@/types'
-
-// DB-backed user settings. These are worth sharing across browsers for one user.
-export type UserSettings = {
-    theme:               'system' | 'light' | 'dark'
-    autoFetchTitle:      'auto' | 'manual' | 'off'
-    autoFetchThumbnail:  'auto' | 'manual' | 'off'
-    wikiEditorMode:      'split' | 'write' | 'preview' }
-
-export type TheatreLayoutMode = 'threeColumns' | 'tagsBottom' | 'commentsBottom'
-export type TheatreTagFlow = 'vertical' | 'horizontal'
-export type GekanatorBackgroundMotionMode = 'on' | 'calm' | 'off'
-export type ClientPaneBreakpoint = 'desktop' | 'tablet'
-export type ClientListKey = 'postList' | 'postSearch' | 'tagList'
-export type ClientListLimit = 20 | 50 | 100
-
-type ClientPaneSettings = {
-    widthPxByBreakpoint?: Partial<Record<ClientPaneBreakpoint, number>>
-    collapsed?:           boolean }
-
-type ClientListSettings = {
-    limit?: ClientListLimit
-    order?: string }
-
-// Browser-local settings. These depend on device or screen context.
-export type ClientSettings = {
-    panes?:          Record<string, ClientPaneSettings>
-    lists?:          Partial<Record<ClientListKey, ClientListSettings>>
-    theatre?:        {
-	layoutMode?: TheatreLayoutMode
-	tagFlow?:    TheatreTagFlow
-    }
-    gekanator?:     {
-	backgroundMotion?: GekanatorBackgroundMotionMode
-    }
-    reducedMotion?: string
-    embedAutoLoad?: string
-    thumbnailMode?: string }
-
-export const CLIENT_SETTINGS_STORAGE_KEY = 'btrc_hub.client_settings'
-export const DEFAULT_USER_SETTINGS: UserSettings = {
-    theme:               'system',
-    autoFetchTitle:      'manual',
-    autoFetchThumbnail:  'manual',
-    wikiEditorMode:      'split' }
-
-export const THEME_OPTIONS = ['system', 'light', 'dark'] as const
-export const AUTO_FETCH_OPTIONS = ['auto', 'manual', 'off'] as const
-export const WIKI_EDITOR_MODE_OPTIONS = ['split', 'write', 'preview'] as const
-export const LIST_LIMIT_OPTIONS = [20, 50, 100] as const
-export const POST_LIST_ORDER_OPTIONS = [
-    'title:asc',
-    'title:desc',
-    'url:asc',
-    'url:desc',
-    'original_created_at:asc',
-    'original_created_at:desc',
-    'created_at:asc',
-    'created_at:desc',
-    'updated_at:asc',
-    'updated_at:desc',
-] as const satisfies readonly FetchPostsOrder[]
-export const TAG_LIST_ORDER_OPTIONS = [
-    'name:asc',
-    'name:desc',
-    'category:asc',
-    'category:desc',
-    'post_count:asc',
-    'post_count:desc',
-    'created_at:asc',
-    'created_at:desc',
-    'updated_at:asc',
-    'updated_at:desc',
-] as const satisfies readonly FetchTagsOrder[]
-export const DEFAULT_POST_LIST_LIMIT: ClientListLimit = 20
-export const DEFAULT_POST_LIST_ORDER: FetchPostsOrder = 'original_created_at:desc'
-export const DEFAULT_TAG_LIST_ORDER: FetchTagsOrder = 'name:asc'
-
-const LEGACY_THEATRE_LAYOUT_STORAGE_KEY = 'theatre-layout-mode'
-const LEGACY_THEATRE_TAG_FLOW_STORAGE_KEY = 'theatre-tag-flow'
-const LEGACY_GEKANATOR_BACKGROUND_MOTION_STORAGE_KEY =
-    'gekanator:background-motion:v1'
-
-
-export const fetchUserSettings = async (): Promise<UserSettings> =>
-    await apiGet<UserSettings> ('/users/settings')
-
-
-export const updateUserSettings = async (
-    settings: Partial<{
-	theme:                 UserSettings['theme']
-	auto_fetch_title:      UserSettings['autoFetchTitle']
-	auto_fetch_thumbnail:  UserSettings['autoFetchThumbnail']
-	wiki_editor_mode:      UserSettings['wikiEditorMode']
-    }>,
-): Promise<UserSettings> => await apiPatch<UserSettings> ('/users/settings', settings)
-
-
-const safeParseClientSettings = (raw: string | null): ClientSettings => {
-  if (!(raw))
-    return { }
-
-  try
-  {
-    const parsed = JSON.parse (raw)
-    return parsed && typeof parsed === 'object' ? parsed as ClientSettings : { }
-  }
-  catch
-  {
-    return { }
-  }
-}
-
-
-export const loadClientSettings = (): ClientSettings =>
-    safeParseClientSettings (localStorage.getItem (CLIENT_SETTINGS_STORAGE_KEY))
-
-
-export const saveClientSettings = (settings: ClientSettings): void => {
-  localStorage.setItem (CLIENT_SETTINGS_STORAGE_KEY, JSON.stringify (settings))
-}
-
-
-export const updateClientSettings = (
-    updater: (settings: ClientSettings) => ClientSettings,
-): ClientSettings => {
-  const next = updater (loadClientSettings ())
-  saveClientSettings (next)
-  return next
-}
-
-
-const validListLimit = (value: unknown): ClientListLimit | null =>
-    value === 20 || value === 50 || value === 100 ? value : null
-
-
-export const getClientListLimit = (
-    listKey: ClientListKey,
-): ClientListLimit | null => {
-  const value = loadClientSettings ().lists?.[listKey]?.limit
-  return validListLimit (value)
-}
-
-
-export const getClientListOrder = <T extends string>(
-    listKey: ClientListKey,
-): T | null => {
-  const value = loadClientSettings ().lists?.[listKey]?.order
-  return typeof value === 'string' ? value as T : null
-}
-
-
-export const setClientListSettings = (
-    listKey: ClientListKey,
-    { limit, order }: { limit?: ClientListLimit
-			order?: string },
-): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      lists: {
-	  ...(settings.lists ?? { }),
-	  [listKey]: {
-	      ...(settings.lists?.[listKey] ?? { }),
-	      ...(limit == null ? { } : { limit }),
-	      ...(order == null ? { } : { order }),
-	  },
-      },
-  }))
-}
-
-
-const legacyTheatreLayoutMode = (): TheatreLayoutMode | null => {
-  const value = localStorage.getItem (LEGACY_THEATRE_LAYOUT_STORAGE_KEY)
-  return (
-      value === 'threeColumns'
-      || value === 'tagsBottom'
-      || value === 'commentsBottom'
-  ) ? value : null
-}
-
-
-const legacyTheatreTagFlow = (): TheatreTagFlow | null => {
-  const value = localStorage.getItem (LEGACY_THEATRE_TAG_FLOW_STORAGE_KEY)
-  return (value === 'vertical' || value === 'horizontal') ? value : null
-}
-
-
-const legacyGekanatorBackgroundMotion = (): GekanatorBackgroundMotionMode | null => {
-  const value = localStorage.getItem (LEGACY_GEKANATOR_BACKGROUND_MOTION_STORAGE_KEY)
-  return (value === 'on' || value === 'calm' || value === 'off') ? value : null
-}
-
-
-export const getClientTheatreLayoutMode = (): TheatreLayoutMode =>
-    loadClientSettings ().theatre?.layoutMode
-    ?? legacyTheatreLayoutMode ()
-    ?? 'threeColumns'
-
-
-export const setClientTheatreLayoutMode = (layoutMode: TheatreLayoutMode): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      theatre: { ...(settings.theatre ?? { }), layoutMode } }))
-}
-
-
-export const getClientTheatreTagFlow = (): TheatreTagFlow =>
-    loadClientSettings ().theatre?.tagFlow
-    ?? legacyTheatreTagFlow ()
-    ?? 'vertical'
-
-
-export const setClientTheatreTagFlow = (tagFlow: TheatreTagFlow): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      theatre: { ...(settings.theatre ?? { }), tagFlow } }))
-}
-
-
-export const getClientGekanatorBackgroundMotion =
-    (): GekanatorBackgroundMotionMode =>
-	loadClientSettings ().gekanator?.backgroundMotion
-	?? legacyGekanatorBackgroundMotion ()
-	?? 'on'
-
-
-export const setClientGekanatorBackgroundMotion = (
-    backgroundMotion: GekanatorBackgroundMotionMode,
-): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      gekanator: { ...(settings.gekanator ?? { }), backgroundMotion } }))
-}
-
-
-export const getClientPaneWidthPx = (
-    paneKey:      string,
-    breakpoint:   ClientPaneBreakpoint,
-): number | null => {
-  const value = loadClientSettings ().panes?.[paneKey]?.widthPxByBreakpoint?.[breakpoint]
-  return typeof value === 'number' ? value : null
-}
-
-
-export const setClientPaneWidthPx = (
-    paneKey:      string,
-    breakpoint:   ClientPaneBreakpoint,
-    widthPx:      number,
-): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      panes: {
-	  ...(settings.panes ?? { }),
-	  [paneKey]: {
-	      ...(settings.panes?.[paneKey] ?? { }),
-	      widthPxByBreakpoint: {
-		  ...(settings.panes?.[paneKey]?.widthPxByBreakpoint ?? { }),
-		  [breakpoint]: widthPx,
-	      },
-	  },
-      },
-  }))
-}
-
-
-export const setClientPaneCollapsed = (
-    paneKey:      string,
-    collapsed:    boolean,
-): void => {
-  updateClientSettings (settings => ({
-      ...settings,
-      panes: {
-	  ...(settings.panes ?? { }),
-	  [paneKey]: {
-	      ...(settings.panes?.[paneKey] ?? { }),
-	      collapsed,
-	  },
-      },
-  }))
-}

frontend/src/pages/GekanatorPage.tsx

@@ -24,10 +24,6 @@ import { recoverCandidatePosts } from '@/lib/gekanatorCandidateRecovery'
 import { isQuestionHardFilteredAfterAnswers,
 	 monthForCondition } from '@/lib/gekanatorQuestionFilters'
 import { gekanatorKeys } from '@/lib/queryKeys'
-import {
-  getClientGekanatorBackgroundMotion,
-  setClientGekanatorBackgroundMotion,
-} from '@/lib/settings'
 import { cn } from '@/lib/utils'
 
 import type { FC } from 'react'
@@ -189,6 +185,7 @@ const softenedAnswerWeight = .35
 const confidenceTemperature = 6
 const gameStorageKey = 'gekanator:game:v1'
 const recentGamesStorageKey = 'gekanator:recent-games:v1'
+const backgroundMotionStorageKey = 'gekanator:background-motion:v1'
 const maxStoredRecentGames = 12
 const specialOriginalMonthDayLabels: Record<string, string> = {
     '1-1': '元日',
@@ -432,13 +429,18 @@ const storeRecentGameSummary = (
 
 
 const loadBackgroundMotionMode = (): BackgroundMotionMode => {
+  const fallbackMode = 'on'
   try
   {
-    return getClientGekanatorBackgroundMotion ()
+    const raw = localStorage.getItem (backgroundMotionStorageKey)
+    if (raw === 'off' || raw === 'calm' || raw === 'on')
+      return raw
+
+    return fallbackMode
   }
   catch
   {
-    return 'on'
+    return fallbackMode
   }
 }
 
@@ -3914,7 +3916,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
   useEffect (() => {
     try
     {
-      setClientGekanatorBackgroundMotion (backgroundMotionMode)
+      localStorage.setItem (backgroundMotionStorageKey, backgroundMotionMode)
     }
     catch
     {

frontend/src/pages/materials/MaterialBasePage.tsx

@@ -6,9 +6,11 @@ import type { FC } from 'react'
 
 
 const MaterialBasePage: FC = () => (
-    <div className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
+    <div
+	data-sidebar-container
+	className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
       <MaterialSidebar/>
       <Outlet/>
     </div>)
 
-export default MaterialBasePage
+export default MaterialBasePage

frontend/src/pages/materials/MaterialNewPage.tsx

@@ -79,7 +79,7 @@ const MaterialNewPage: FC = () => {
 	  <FieldError messages={baseErrors}/>
 
 	  {/* タグ */}
-	   <FormField label="タグ" messages={fieldErrors.tag}>
+	  <FormField label="タグ" messages={fieldErrors.tag}>
 	    {({ describedBy, invalid }) => (
 		<TagInput
 		    describedBy={describedBy}

frontend/src/pages/posts/PostDetailPage.tsx

@@ -92,16 +92,16 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 		       : 'bg-gray-500 hover:bg-gray-600')
 
   return (
-      <div className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
+      <div
+	  data-sidebar-container
+	  className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
 	<Helmet>
 	  {(post?.thumbnail || post?.thumbnailBase) && (
 	      <meta name="thumbnail" content={post.thumbnail! || post.thumbnailBase!}/>)}
 	  {post && <title>{`${ post.title || post.url } | ${ SITE_TITLE }`}</title>}
 	</Helmet>
 
-	<div className="hidden md:block">
+	{post && <TagDetailSidebar post={post} className="hidden md:block"/>}
-	  {post && <TagDetailSidebar post={post}/>}
-	</div>
 
 	<MainArea className="relative">
 	  {post
@@ -179,9 +179,7 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 	   : 'Loading...'}
 	</MainArea>
 
-	<div className="md:hidden">
+	{post && <TagDetailSidebar post={post} sp className="md:hidden"/>}
-	  {post && <TagDetailSidebar post={post} sp/>}
-	</div>
       </div>)
 }
 

frontend/src/pages/posts/PostListPage.tsx

@@ -1,57 +1,23 @@
 import { useQuery } from '@tanstack/react-query'
-import { useEffect, useLayoutEffect, useMemo, useRef, useState } from 'react'
+import { useLayoutEffect, useMemo, useRef, useState } from 'react'
 import { Helmet } from 'react-helmet-async'
-import { useLocation, useNavigate } from 'react-router-dom'
+import { useLocation } from 'react-router-dom'
 
 import PostList from '@/components/PostList'
 import PrefetchLink from '@/components/PrefetchLink'
 import TagSidebar from '@/components/TagSidebar'
 import WikiBody from '@/components/WikiBody'
-import FormField from '@/components/common/FormField'
 import Pagination from '@/components/common/Pagination'
 import TabGroup, { Tab } from '@/components/common/TabGroup'
 import MainArea from '@/components/layout/MainArea'
 import { SITE_TITLE } from '@/config'
 import { fetchPosts } from '@/lib/posts'
 import { postsKeys } from '@/lib/queryKeys'
-import {
-    DEFAULT_POST_LIST_LIMIT,
-    DEFAULT_POST_LIST_ORDER,
-    getClientListLimit,
-    getClientListOrder,
-    LIST_LIMIT_OPTIONS,
-    POST_LIST_ORDER_OPTIONS,
-    setClientListSettings,
-} from '@/lib/settings'
-import { inputClass } from '@/lib/utils'
 import { fetchWikiPageByTitle } from '@/lib/wiki'
 
 import type { FC } from 'react'
 
-import type { FetchPostsOrder, WikiPage } from '@/types'
+import type { WikiPage } from '@/types'
-
-const postOrderLabel: Record<FetchPostsOrder, string> = {
-    'title:asc': 'タイトル昇順',
-    'title:desc': 'タイトル降順',
-    'url:asc': 'URL 昇順',
-    'url:desc': 'URL 降順',
-    'original_created_at:asc': 'オリジナル投稿日時 昇順',
-    'original_created_at:desc': 'オリジナル投稿日時 降順',
-    'created_at:asc': '投稿日 昇順',
-    'created_at:desc': '投稿日 降順',
-    'updated_at:asc': '更新日 昇順',
-    'updated_at:desc': '更新日 降順',
-}
-
-const parseLimit = (value: string | null): 20 | 50 | 100 | null => {
-  const n = Number (value)
-  return n === 20 || n === 50 || n === 100 ? n : null
-}
-
-const parseOrder = (value: string | null): FetchPostsOrder | null =>
-    POST_LIST_ORDER_OPTIONS.some (option => option === value)
-    ? value as FetchPostsOrder
-    : null
 
 
 const PostListPage: FC = () => {
@@ -60,7 +26,6 @@ const PostListPage: FC = () => {
   const [wikiPage, setWikiPage] = useState<WikiPage | null> (null)
 
   const location = useLocation ()
-  const navigate = useNavigate ()
   const query = new URLSearchParams (location.search)
   const tagsQuery = query.get ('tags') ?? ''
   const anyFlg = query.get ('match') === 'any'
@@ -68,22 +33,13 @@ const PostListPage: FC = () => {
   const tags = useMemo (() => tagsQuery.split (' ').filter (e => e !== ''), [tagsQuery])
   const tagsKey = tags.join (' ')
   const page = Number (query.get ('page') ?? 1)
-  const limit = (
+  const limit = Number (query.get ('limit') ?? 20)
-      parseLimit (query.get ('limit'))
-      ?? getClientListLimit ('postList')
-      ?? DEFAULT_POST_LIST_LIMIT
-  )
-  const order = (
-      parseOrder (query.get ('order'))
-      ?? getClientListOrder<FetchPostsOrder> ('postList')
-      ?? DEFAULT_POST_LIST_ORDER
-  )
 
   const keys = {
       tags: tagsKey, match, page, limit,
       url: '', title: '', originalCreatedFrom: '', originalCreatedTo: '',
       createdFrom: '', createdTo: '', updatedFrom: '', updatedTo: '',
-      order } as const
+      order: 'original_created_at:desc' } as const
   const { data, isLoading: loading } = useQuery ({
       queryKey: postsKeys.index (keys),
       queryFn:  () => fetchPosts (keys) })
@@ -91,19 +47,6 @@ const PostListPage: FC = () => {
   const cursor = ''
   const totalPages = data ? Math.ceil (data.count / limit) : 0
 
-  useEffect (() => {
-    setClientListSettings ('postList', { limit, order })
-  }, [limit, order])
-
-  const updateListQuery = (next: { limit?: 20 | 50 | 100
-				   order?: FetchPostsOrder }) => {
-    const params = new URLSearchParams (location.search)
-    params.set ('limit', String (next.limit ?? limit))
-    params.set ('order', next.order ?? order)
-    params.set ('page', '1')
-    navigate (`${ location.pathname }?${ params.toString () }`)
-  }
-
   useLayoutEffect (() => {
     scroll (0, 0)
 
@@ -127,6 +70,7 @@ const PostListPage: FC = () => {
 
   return (
       <div
+	  data-sidebar-container
 	  className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden"
 	  ref={containerRef}>
 	<Helmet>
@@ -146,38 +90,6 @@ const PostListPage: FC = () => {
 	}}/>
 
 	<MainArea>
-	  <div className="mb-4 flex flex-wrap gap-4 rounded-xl border border-border bg-background/80 p-4">
-	    <FormField label="表示件数">
-	      {() => (
-		  <select
-		      className={inputClass (false)}
-		      value={limit}
-		      onChange={ev => updateListQuery ({
-			  limit: Number (ev.target.value) as 20 | 50 | 100,
-		      })}>
-		    {LIST_LIMIT_OPTIONS.map (value => (
-			<option key={value} value={value}>
-			  {value} 件
-			</option>))}
-		  </select>)}
-	    </FormField>
-
-	    <FormField label="並び順">
-	      {() => (
-		  <select
-		      className={inputClass (false)}
-		      value={order}
-		      onChange={ev => updateListQuery ({
-			  order: ev.target.value as FetchPostsOrder,
-		      })}>
-		    {POST_LIST_ORDER_OPTIONS.map (value => (
-			<option key={value} value={value}>
-			  {postOrderLabel[value]}
-			</option>))}
-		  </select>)}
-	    </FormField>
-	  </div>
-
 	  <TabGroup>
 	    <Tab name="広場">
 	      {posts.length > 0

frontend/src/pages/posts/PostNewPage.tsx

@@ -9,7 +9,6 @@ import Form from '@/components/common/Form'
 import FormField from '@/components/common/FormField'
 import PageTitle from '@/components/common/PageTitle'
 import MainArea from '@/components/layout/MainArea'
-import { useUserSettings } from '@/components/users/UserSettingsProvider'
 import { Button } from '@/components/ui/button'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
@@ -31,7 +30,6 @@ type PostFormField =
 
 const PostNewPage: FC<Props> = ({ user }) => {
   const editable = canEditContent (user)
-  const { settings } = useUserSettings ()
 
   const navigate = useNavigate ()
 
@@ -43,22 +41,17 @@ const PostNewPage: FC<Props> = ({ user }) => {
   const [parentPostIds, setParentPostIds] = useState ('')
   const [tags, setTags] = useState ('')
   const [duration, setDuration] = useState ('')
+  const [thumbnailAutoFlg, setThumbnailAutoFlg] = useState (true)
   const [thumbnailFile, setThumbnailFile] = useState<File | null> (null)
   const [thumbnailLoading, setThumbnailLoading] = useState (false)
   const [thumbnailPreview, setThumbnailPreview] = useState<string> ('')
   const [title, setTitle] = useState ('')
+  const [titleAutoFlg, setTitleAutoFlg] = useState (true)
   const [titleLoading, setTitleLoading] = useState (false)
   const [url, setURL] = useState ('')
-  const [titleAutoFlg, setTitleAutoFlg] = useState (settings.autoFetchTitle === 'auto')
-  const [thumbnailAutoFlg, setThumbnailAutoFlg] =
-      useState (settings.autoFetchThumbnail === 'auto')
 
   const previousURLRef = useRef ('')
   const thumbnailPreviewRef = useRef ('')
-  const titleFetchMode = settings.autoFetchTitle
-  const thumbnailFetchMode = settings.autoFetchThumbnail
-  const titleFetchVisible = titleFetchMode !== 'off'
-  const thumbnailFetchVisible = thumbnailFetchMode !== 'off'
   const videoFlg =
       useMemo (() => tags.split (/\s+/).some (tag => tag.replace (/\[.*\]$/, '') === '動画'),
                [tags])
@@ -107,15 +100,9 @@ const PostNewPage: FC<Props> = ({ user }) => {
   const fetchTitle = useCallback (async () => {
     setTitle ('')
     setTitleLoading (true)
-    try
+    const data = await apiGet<{ title: string }> ('/preview/title', { params: { url } })
-    {
+    setTitle (data.title || '')
-      const data = await apiGet<{ title: string }> ('/preview/title', { params: { url } })
+    setTitleLoading (false)
-      setTitle (data.title || '')
-    }
-    finally
-    {
-      setTitleLoading (false)
-    }
   }, [url])
 
   const fetchThumbnail = useCallback (async () => {
@@ -124,34 +111,20 @@ const PostNewPage: FC<Props> = ({ user }) => {
     setThumbnailLoading (true)
     if (thumbnailPreviewRef.current)
       URL.revokeObjectURL (thumbnailPreviewRef.current)
-    try
+    const data = await apiGet<Blob> ('/preview/thumbnail',
-    {
+				     { params: { url }, responseType: 'blob' })
-      const data = await apiGet<Blob> ('/preview/thumbnail',
+    const imageURL = URL.createObjectURL (data)
-				       { params: { url }, responseType: 'blob' })
+    setThumbnailPreview (imageURL)
-      const imageURL = URL.createObjectURL (data)
+    setThumbnailFile (new File ([data],
-      setThumbnailPreview (imageURL)
+				'thumbnail.png',
-      setThumbnailFile (new File ([data],
+				{ type: data.type || 'image/png' }))
-				  'thumbnail.png',
+    setThumbnailLoading (false)
-				  { type: data.type || 'image/png' }))
-    }
-    finally
-    {
-      setThumbnailLoading (false)
-    }
   }, [url])
 
   useEffect (() => {
     thumbnailPreviewRef.current = thumbnailPreview
   }, [thumbnailPreview])
 
-  useEffect (() => {
-    setTitleAutoFlg (settings.autoFetchTitle === 'auto')
-  }, [settings.autoFetchTitle])
-
-  useEffect (() => {
-    setThumbnailAutoFlg (settings.autoFetchThumbnail === 'auto')
-  }, [settings.autoFetchThumbnail])
-
   useEffect (() => {
     if (titleAutoFlg && url)
       fetchTitle ()
@@ -188,78 +161,34 @@ const PostNewPage: FC<Props> = ({ user }) => {
 	  </FormField>
 
 	  {/* タイトル */}
-	  <FormField label="タイトル" messages={fieldErrors.title}>
+	  <FormField
+	      checkBox={{
+		  label:    '自動',
+		  checked:  titleAutoFlg,
+		  onChange: ev => setTitleAutoFlg (ev.target.checked)}}
+	      label="タイトル"
+	      messages={fieldErrors.title}>
 	    {({ describedBy, invalid }) => (
-		<div className="space-y-2">
+		<input type="text"
-		  <input type="text"
+		       aria-describedby={describedBy}
-			 aria-describedby={describedBy}
+		       aria-invalid={invalid}
-			 aria-invalid={invalid}
+		       className={inputClass (invalid)}
-			 className={inputClass (invalid)}
+		       value={title}
-			 value={title}
+		       placeholder={titleLoading ? 'Loading...' : ''}
-			 placeholder={titleLoading ? 'Loading...' : ''}
+		       onChange={ev => setTitle (ev.target.value)}
-			 onChange={ev => setTitle (ev.target.value)}
+		       disabled={titleAutoFlg}/>)}
-			 disabled={titleLoading}/>
-		  <div className="flex flex-wrap items-center gap-2 text-sm">
-		    <span>
-		      {titleAutoFlg
-		       ? 'URL 入力時に自動取得します．'
-		       : titleFetchMode === 'manual'
-			 ? '自動取得しません．必要なら手動で取得できます．'
-		       : '取得機能は無効です．'}
-		    </span>
-		    {titleFetchVisible && (
-			<>
-			  <label className="flex items-center gap-1">
-			    <input
-				type="checkbox"
-				checked={titleAutoFlg}
-				onChange={ev => setTitleAutoFlg (ev.target.checked)}/>
-			    <span>自動</span>
-			  </label>
-			  {!(titleAutoFlg) && (
-			      <Button
-				  type="button"
-				  variant="outline"
-				  onClick={() => void fetchTitle ()}
-				  disabled={!(url) || titleLoading}>
-				取得
-			      </Button>)}
-			</>)}
-		  </div>
-		</div>)}
 	  </FormField>
 
 	  {/* サムネール */}
-	  <FormField label="サムネール" messages={fieldErrors.thumbnail}>
+	  <FormField
+	      checkBox={{
+		  label:    '自動',
+		  checked:  thumbnailAutoFlg,
+		  onChange: ev => setThumbnailAutoFlg (ev.target.checked)}}
+	      label="サムネール"
+	      messages={fieldErrors.thumbnail}>
 	    {({ describedBy, invalid }) => (
 		<>
-		  <div className="mb-2 flex flex-wrap items-center gap-2 text-sm">
-		    <span>
-		      {thumbnailAutoFlg
-		       ? 'URL 入力時に自動取得します．'
-		       : thumbnailFetchMode === 'manual'
-			 ? '自動取得しません．必要なら手動で取得できます．'
-		       : '取得機能は無効です．'}
-		    </span>
-		    {thumbnailFetchVisible && (
-			<>
-			  <label className="flex items-center gap-1">
-			    <input
-				type="checkbox"
-				checked={thumbnailAutoFlg}
-				onChange={ev => setThumbnailAutoFlg (ev.target.checked)}/>
-			    <span>自動</span>
-			  </label>
-			  {!(thumbnailAutoFlg) && (
-			      <Button
-				  type="button"
-				  variant="outline"
-				  onClick={() => void fetchThumbnail ()}
-				  disabled={!(url) || thumbnailLoading}>
-				取得
-			      </Button>)}
-			</>)}
-		  </div>
 		  {thumbnailAutoFlg
 		   ? (thumbnailLoading
 		      ? <p className="text-gray-500 text-sm">Loading...</p>

frontend/src/pages/posts/PostSearchPage.tsx

@@ -16,15 +16,6 @@ import MainArea from '@/components/layout/MainArea'
 import { SITE_TITLE } from '@/config'
 import { fetchPosts } from '@/lib/posts'
 import { postsKeys } from '@/lib/queryKeys'
-import {
-    DEFAULT_POST_LIST_LIMIT,
-    DEFAULT_POST_LIST_ORDER,
-    getClientListLimit,
-    getClientListOrder,
-    LIST_LIMIT_OPTIONS,
-    POST_LIST_ORDER_OPTIONS,
-    setClientListSettings,
-} from '@/lib/settings'
 import { dateString, inputClass, originalCreatedAtString } from '@/lib/utils'
 
 import type { FC, FormEvent } from 'react'
@@ -40,29 +31,6 @@ const setIf = (qs: URLSearchParams, k: string, v: string | null) => {
     qs.set (k, t)
 }
 
-const postOrderLabel: Record<FetchPostsOrder, string> = {
-    'title:asc': 'タイトル昇順',
-    'title:desc': 'タイトル降順',
-    'url:asc': 'URL 昇順',
-    'url:desc': 'URL 降順',
-    'original_created_at:asc': 'オリジナル投稿日時 昇順',
-    'original_created_at:desc': 'オリジナル投稿日時 降順',
-    'created_at:asc': '投稿日 昇順',
-    'created_at:desc': '投稿日 降順',
-    'updated_at:asc': '更新日 昇順',
-    'updated_at:desc': '更新日 降順',
-}
-
-const parseLimit = (value: string | null): 20 | 50 | 100 | null => {
-  const n = Number (value)
-  return n === 20 || n === 50 || n === 100 ? n : null
-}
-
-const parseOrder = (value: string | null): FetchPostsOrder | null =>
-    POST_LIST_ORDER_OPTIONS.some (option => option === value)
-    ? value as FetchPostsOrder
-    : null
-
 
 const PostSearchPage: FC = () => {
   const location = useLocation ()
@@ -73,11 +41,7 @@ const PostSearchPage: FC = () => {
 			 [location.search])
 
   const page = Number (query.get ('page') ?? 1)
-  const limit = (
+  const limit = Number (query.get ('limit') ?? 20)
-      parseLimit (query.get ('limit'))
-      ?? getClientListLimit ('postSearch')
-      ?? DEFAULT_POST_LIST_LIMIT
-  )
 
   const qURL = query.get ('url') ?? ''
   const qTitle = query.get ('title') ?? ''
@@ -89,11 +53,7 @@ const PostSearchPage: FC = () => {
   const qCreatedTo = query.get ('created_to') ?? ''
   const qUpdatedFrom = query.get ('updated_from') ?? ''
   const qUpdatedTo = query.get ('updated_to') ?? ''
-  const order = (
+  const order = (query.get ('order') || 'original_created_at:desc') as FetchPostsOrder
-      parseOrder (query.get ('order'))
-      ?? getClientListOrder<FetchPostsOrder> ('postSearch')
-      ?? DEFAULT_POST_LIST_ORDER
-  )
 
   const [createdFrom, setCreatedFrom] = useState<string | null> (null)
   const [createdTo, setCreatedTo] = useState<string | null> (null)
@@ -123,10 +83,6 @@ const PostSearchPage: FC = () => {
   const results = data?.posts ?? []
   const totalPages = data ? Math.ceil (data.count / limit) : 0
 
-  useEffect (() => {
-    setClientListSettings ('postSearch', { limit, order })
-  }, [limit, order])
-
   useEffect (() => {
     setURL (qURL ?? '')
     setTitle (qTitle ?? '')
@@ -157,16 +113,6 @@ const PostSearchPage: FC = () => {
     qs.set ('match', matchType)
     qs.set ('page', '1')
     qs.set ('order', order)
-    qs.set ('limit', String (limit))
-    navigate (`${ location.pathname }?${ qs.toString () }`)
-  }
-
-  const updateListQuery = (next: { limit?: 20 | 50 | 100
-				   order?: FetchPostsOrder }) => {
-    const qs = new URLSearchParams (location.search)
-    qs.set ('limit', String (next.limit ?? limit))
-    qs.set ('order', next.order ?? order)
-    qs.set ('page', '1')
     navigate (`${ location.pathname }?${ qs.toString () }`)
   }
 
@@ -191,38 +137,6 @@ const PostSearchPage: FC = () => {
 	  <PageTitle>広場検索</PageTitle>
 
 	  <form onSubmit={handleSearch} className="space-y-2">
-	    <div className="grid gap-3 rounded-xl border border-border bg-background/80 p-3 sm:grid-cols-2">
-	      <FormField label="表示件数">
-		{() => (
-		    <select
-			className={inputClass (false)}
-			value={limit}
-			onChange={ev => updateListQuery ({
-			    limit: Number (ev.target.value) as 20 | 50 | 100,
-			})}>
-		      {LIST_LIMIT_OPTIONS.map (value => (
-			  <option key={value} value={value}>
-			    {value} 件
-			  </option>))}
-		    </select>)}
-	      </FormField>
-
-	      <FormField label="並び順">
-		{() => (
-		    <select
-			className={inputClass (false)}
-			value={order}
-			onChange={ev => updateListQuery ({
-			    order: ev.target.value as FetchPostsOrder,
-			})}>
-		      {POST_LIST_ORDER_OPTIONS.map (value => (
-			  <option key={value} value={value}>
-			    {postOrderLabel[value]}
-			  </option>))}
-		    </select>)}
-	      </FormField>
-	    </div>
-
 	    {/* タイトル */}
 	    <FormField label="タイトル">
 	      {({ invalid }) => (
@@ -247,7 +161,6 @@ const PostSearchPage: FC = () => {
 	    <FormField label="タグ">
 	      {() => (
 		  <TagInput
-		      includeNico={true}
 		      value={tagsStr}
 		      setValue={setTagsStr}/>)}
 	    </FormField>
@@ -383,9 +296,7 @@ const PostSearchPage: FC = () => {
 		  </thead>
 		  <tbody>
 		    {results.map (row => (
-			<tr
+			<tr key={row.id} className="even:bg-gray-100 dark:even:bg-gray-700">
-			    key={row.id}
-			    className="even:bg-gray-100 dark:even:bg-gray-700">
 			  <td className="p-2">
 			    <PrefetchLink to={`/posts/${ row.id }`} title={row.title || undefined}>
 			      <motion.div

frontend/src/pages/tags/TagListPage.tsx

@@ -14,15 +14,6 @@ import MainArea from '@/components/layout/MainArea'
 import { SITE_TITLE } from '@/config'
 import { CATEGORIES, CATEGORY_NAMES } from '@/consts'
 import { tagsKeys } from '@/lib/queryKeys'
-import {
-    DEFAULT_POST_LIST_LIMIT,
-    DEFAULT_TAG_LIST_ORDER,
-    getClientListLimit,
-    getClientListOrder,
-    LIST_LIMIT_OPTIONS,
-    setClientListSettings,
-    TAG_LIST_ORDER_OPTIONS,
-} from '@/lib/settings'
 import { fetchTags } from '@/lib/tags'
 import { dateString, inputClass } from '@/lib/utils'
 
@@ -44,29 +35,6 @@ const boolFromQuery = (value: string | null): boolean =>
 
 const tagStateLabel = (deprecatedAt: string | null) => deprecatedAt ? '廃止' : ''
 
-const tagOrderLabel: Record<FetchTagsOrder, string> = {
-    'name:asc': '名前昇順',
-    'name:desc': '名前降順',
-    'category:asc': 'カテゴリ昇順',
-    'category:desc': 'カテゴリ降順',
-    'post_count:asc': '件数昇順',
-    'post_count:desc': '件数降順',
-    'created_at:asc': '最初の記載日時 昇順',
-    'created_at:desc': '最初の記載日時 降順',
-    'updated_at:asc': '更新日時 昇順',
-    'updated_at:desc': '更新日時 降順',
-}
-
-const parseLimit = (value: string | null): 20 | 50 | 100 | null => {
-  const n = Number (value)
-  return n === 20 || n === 50 || n === 100 ? n : null
-}
-
-const parseOrder = (value: string | null): FetchTagsOrder | null =>
-    TAG_LIST_ORDER_OPTIONS.some (option => option === value)
-    ? value as FetchTagsOrder
-    : null
-
 
 const TagListPage: FC = () => {
   const location = useLocation ()
@@ -76,11 +44,7 @@ const TagListPage: FC = () => {
   const query = useMemo (() => new URLSearchParams (location.search), [location.search])
 
   const page = Number (query.get ('page') ?? 1)
-  const limit = (
+  const limit = Number (query.get ('limit') ?? 20)
-      parseLimit (query.get ('limit'))
-      ?? getClientListLimit ('tagList')
-      ?? DEFAULT_POST_LIST_LIMIT
-  )
 
   const qName = query.get ('name') ?? ''
   const qCategory = (query.get ('category') || null) as Category | null
@@ -94,11 +58,7 @@ const TagListPage: FC = () => {
   const qDeprecated = query.has ('deprecated')
       ? boolFromQuery (query.get ('deprecated'))
       : null
-  const order = (
+  const order = (query.get ('order') || 'post_count:desc') as FetchTagsOrder
-      parseOrder (query.get ('order'))
-      ?? getClientListOrder<FetchTagsOrder> ('tagList')
-      ?? DEFAULT_TAG_LIST_ORDER
-  )
 
   const [name, setName] = useState ('')
   const [category, setCategory] = useState<Category | null> (null)
@@ -128,10 +88,6 @@ const TagListPage: FC = () => {
   const results = data?.tags ?? []
   const totalPages = data ? Math.ceil (data.count / limit) : 0
 
-  useEffect (() => {
-    setClientListSettings ('tagList', { limit, order })
-  }, [limit, order])
-
   useEffect (() => {
     setName (qName)
     setCategory (qCategory)
@@ -165,20 +121,10 @@ const TagListPage: FC = () => {
       qs.set ('deprecated', deprecated ? '1' : '0')
     qs.set ('page', '1')
     qs.set ('order', order)
-    qs.set ('limit', String (limit))
 
     navigate (`${ location.pathname }?${ qs.toString () }`)
   }
 
-  const updateListQuery = (next: { limit?: 20 | 50 | 100
-				   order?: FetchTagsOrder }) => {
-    const qs = new URLSearchParams (location.search)
-    qs.set ('limit', String (next.limit ?? limit))
-    qs.set ('order', next.order ?? order)
-    qs.set ('page', '1')
-    navigate (`${ location.pathname }?${ qs.toString () }`)
-  }
-
   const defaultDirection = { name: 'asc',
 			     category: 'asc',
 			     post_count: 'desc',
@@ -195,38 +141,6 @@ const TagListPage: FC = () => {
 	  <PageTitle>タグ</PageTitle>
 
 	  <form onSubmit={handleSearch} className="space-y-2">
-	    <div className="grid gap-3 rounded-xl border border-border bg-background/80 p-3 sm:grid-cols-2">
-	      <FormField label="表示件数">
-		{() => (
-		    <select
-			value={limit}
-			onChange={ev => updateListQuery ({
-			    limit: Number (ev.target.value) as 20 | 50 | 100,
-			})}
-			className={inputClass (false)}>
-		      {LIST_LIMIT_OPTIONS.map (value => (
-			  <option key={value} value={value}>
-			    {value} 件
-			  </option>))}
-		    </select>)}
-	      </FormField>
-
-	      <FormField label="並び順">
-		{() => (
-		    <select
-			value={order}
-			onChange={ev => updateListQuery ({
-			    order: ev.target.value as FetchTagsOrder,
-			})}
-			className={inputClass (false)}>
-		      {TAG_LIST_ORDER_OPTIONS.map (value => (
-			  <option key={value} value={value}>
-			    {tagOrderLabel[value]}
-			  </option>))}
-		    </select>)}
-	      </FormField>
-	    </div>
-
 	    {/* 名前 */}
 	    <FormField label="名前">
 	      {({ invalid }) => (

frontend/src/pages/theatres/TheatreDetailPage.test.tsx

@@ -105,6 +105,20 @@ const tagSection = (): HTMLElement =>
   screen.getAllByRole ('heading', { name: 'タグ' })[0].closest ('section')!
 
 const mockDefaultApi = () => {
+  let commentsFetched = false
+  let currentTheatreInfo = buildTheatreInfo ({
+    postId:        currentPost.id,
+    postStartedAt: '2026-01-02T03:04:05.000Z',
+    postElapsedMs: 1_000,
+    watchingUsers,
+    skipVote:      {
+      votesCount:         0,
+      requiredCount:      2,
+      watchingUsersCount: watchingUsers.length,
+      voted:              false,
+    },
+  })
+
   api.apiGet.mockImplementation ((path: string) => {
     switch (path)
     {
@@ -112,13 +126,17 @@ const mockDefaultApi = () => {
       return Promise.resolve (theatre)
 
     case '/theatres/7/comments':
+      if (commentsFetched)
+	return Promise.resolve ([])
+
+      commentsFetched = true
       return Promise.resolve ([
-        buildTheatreComment ({
+	  buildTheatreComment ({
-          theatreId: 7,
+	    theatreId: 7,
-          no:        2,
+	    no:        2,
-          user:      { id: 1, name: 'tester' },
+	    user:      { id: 1, name: 'tester' },
-          content:   '視聴コメント',
+	    content:   '視聴コメント',
-        }),
+	  }),
       ])
 
     case '/theatres/7/programmes':
@@ -136,32 +154,22 @@ const mockDefaultApi = () => {
     switch (path)
     {
     case '/theatres/7/watching':
-      return Promise.resolve (buildTheatreInfo ({
+      return Promise.resolve (currentTheatreInfo)
-        postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 1_000,
-        watchingUsers,
-        skipVote:      {
-          votesCount:         0,
-          requiredCount:      2,
-          watchingUsersCount: watchingUsers.length,
-          voted:              false,
-        },
-      }))
 
     case '/theatres/7/skip_vote':
-      return Promise.resolve (buildTheatreInfo ({
+      currentTheatreInfo = buildTheatreInfo ({
-        postId:        currentPost.id,
+	postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
+	postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 2_000,
+	postElapsedMs: 2_000,
-        watchingUsers,
+	watchingUsers,
-        skipVote:      {
+	skipVote:      {
-          votesCount:         1,
+	  votesCount:         1,
-          requiredCount:      2,
+	  requiredCount:      2,
-          watchingUsersCount: watchingUsers.length,
+	  watchingUsersCount: watchingUsers.length,
-          voted:              true,
+	  voted:              true,
-        },
+	},
-      }))
+      })
+      return Promise.resolve (currentTheatreInfo)
 
     default:
       return Promise.reject (new Error (`Unexpected PUT ${ path }`))

frontend/src/pages/theatres/TheatreDetailPage.tsx

@@ -10,17 +10,12 @@ import PrefetchLink from '@/components/PrefetchLink'
 import TagLink from '@/components/TagLink'
 import FieldError from '@/components/common/FieldError'
 import { useDialogue } from '@/components/dialogues/DialogueProvider'
+import SidebarComponent from '@/components/layout/SidebarComponent'
 import { Button } from '@/components/ui/button'
 import { SITE_TITLE } from '@/config'
 import { CATEGORIES, CATEGORY_NAMES } from '@/consts'
 import { apiDelete, apiGet, apiPatch, apiPost, apiPut, isApiError } from '@/lib/api'
 import { fetchPost } from '@/lib/posts'
-import {
-  getClientTheatreLayoutMode,
-  getClientTheatreTagFlow,
-  setClientTheatreLayoutMode,
-  setClientTheatreTagFlow,
-} from '@/lib/settings'
 import { canEditContent } from '@/lib/users'
 import { cn, dateString, inputClass } from '@/lib/utils'
 import { useValidationErrors } from '@/lib/useValidationErrors'
@@ -56,6 +51,11 @@ const INITIAL_THEATRE_INFO: TheatreInfo =
 const INITIAL_WEIGHTS: TheatrePostSelectionWeights =
     { tagPenalties: [], lightestPosts: [], heaviestPosts: [] }
 
+const LAYOUT_STORAGE_KEY = 'theatre-layout-mode'
+const TAG_FLOW_STORAGE_KEY = 'theatre-tag-flow'
+const MIN_MAIN_WIDTH = 360
+const SIDEBAR_GAP_WIDTH = 16
+
 const LAYOUT_LABELS: Record<TheatreLayoutMode, string> = {
     threeColumns:   '3 列',
     tagsBottom:     '2 列 A 型',
@@ -214,11 +214,16 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
   const commentsRef = useRef<HTMLDivElement> (null)
   const embedRef = useRef<NiconicoViewerHandle> (null)
   const loadingRef = useRef (false)
+  const sidebarContainerRef = useRef<HTMLDivElement> (null)
   const theatreInfoRef = useRef<TheatreInfo> (INITIAL_THEATRE_INFO)
   const theatreInfoReceivedAtRef = useRef (performance.now ())
   const videoLengthRef = useRef (0)
   const lastCommentNoRef = useRef (0)
 
+  const [leftSidebarWidth, setLeftSidebarWidth] = useState (256)
+  const [rightSidebarWidth, setRightSidebarWidth] = useState (256)
+  const [sidebarContainerWidth, setSidebarContainerWidth] = useState (
+      () => typeof window === 'undefined' ? 0 : window.innerWidth)
   const [comments, setComments] = useState<TheatreComment[]> ([])
   const [content, setContent] = useState ('')
   const [editingPost, setEditingPost] = useState<Post | null> (null)
@@ -231,24 +236,37 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
   const [post, setPost] = useState<Post | null> (null)
   const [videoLength, setVideoLength] = useState (0)
   const [weights, setWeights] = useState<TheatrePostSelectionWeights> (INITIAL_WEIGHTS)
-  const [layoutMode, setLayoutMode] =
+  const [layoutMode, setLayoutMode] = useState<TheatreLayoutMode> (() => {
-      useState<TheatreLayoutMode> (() => getClientTheatreLayoutMode ())
+    const stored = localStorage.getItem (LAYOUT_STORAGE_KEY)
-  const [tagFlow, setTagFlow] = useState<TagFlow> (() => getClientTheatreTagFlow ())
+    return (
+	((['threeColumns', 'tagsBottom', 'commentsBottom'] as TheatreLayoutMode[])
+	 .includes (stored as TheatreLayoutMode))
+	? (stored as TheatreLayoutMode)
+	: 'threeColumns')
+  })
+  const [tagFlow, setTagFlow] = useState<TagFlow> (() => {
+    const stored = localStorage.getItem (TAG_FLOW_STORAGE_KEY)
+    return (
+	(['vertical', 'horizontal'] as TagFlow[]).includes (stored as TagFlow)
+	? (stored as TagFlow)
+	: 'vertical')
+  })
   const { fieldErrors, clearValidationErrors, applyValidationError } =
       useValidationErrors<TheatreCommentField> ()
 
   const changeLayoutMode = (mode: TheatreLayoutMode) => {
     setLayoutMode (mode)
-    setClientTheatreLayoutMode (mode)
+    localStorage.setItem (LAYOUT_STORAGE_KEY, mode)
   }
 
   const changeTagFlow = (flow: TagFlow) => {
     setTagFlow (flow)
-    setClientTheatreTagFlow (flow)
+    localStorage.setItem (TAG_FLOW_STORAGE_KEY, flow)
   }
 
   const applyTheatreInfo = useCallback ((nextInfo: TheatreInfo) => {
     theatreInfoReceivedAtRef.current = performance.now ()
+    theatreInfoRef.current = nextInfo
     setTheatreInfo (nextInfo)
   }, [])
 
@@ -315,6 +333,17 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     lastCommentNoRef.current = comments[0]?.no ?? 0
   }, [comments])
 
+  useEffect (() => {
+    const updateSidebarContainerWidth = () => {
+      const nextWidth = sidebarContainerRef.current?.clientWidth ?? window.innerWidth
+      setSidebarContainerWidth (nextWidth)
+    }
+
+    updateSidebarContainerWidth ()
+    window.addEventListener ('resize', updateSidebarContainerWidth)
+    return () => window.removeEventListener ('resize', updateSidebarContainerWidth)
+  }, [])
+
   useEffect (() => {
     if (!(id))
       return
@@ -378,6 +407,9 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	    setComments (prev => [...newComments, ...prev])
 	  }
 
+	if (loadingRef.current)
+	  return
+
 	const currentInfo = theatreInfoRef.current
 	const ended =
 	    currentInfo.hostFlg
@@ -399,8 +431,9 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	    return
 	  }
 
+	const watchingRequestedAt = performance.now ()
 	const nextInfo = await apiPut<TheatreInfo> (`/theatres/${ id }/watching`)
-	if (!(cancelled))
+	if (!(cancelled) && watchingRequestedAt >= theatreInfoReceivedAtRef.current)
 	  applyTheatreInfo (nextInfo)
       }
       catch (error)
@@ -529,6 +562,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     if (!(id) || !(post))
       return
 
+    loadingRef.current = true
     setLoading (true)
     try
     {
@@ -557,6 +591,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     }
     finally
     {
+      loadingRef.current = false
       setLoading (false)
     }
   }
@@ -630,6 +665,26 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
   if (status >= 400)
     return <ErrorScreen status={status}/>
 
+  const singleSidebarMaxWidth = Math.max (
+      192,
+      sidebarContainerWidth - MIN_MAIN_WIDTH - SIDEBAR_GAP_WIDTH)
+  const leftSidebarMaxWidth = layoutMode === 'threeColumns'
+			      ? Math.max (
+				  192,
+				  sidebarContainerWidth
+				  - rightSidebarWidth
+				  - MIN_MAIN_WIDTH
+				  - SIDEBAR_GAP_WIDTH * 2)
+			      : singleSidebarMaxWidth
+  const rightSidebarMaxWidth = layoutMode === 'threeColumns'
+			       ? Math.max (
+				   192,
+				   sidebarContainerWidth
+				   - leftSidebarWidth
+				   - MIN_MAIN_WIDTH
+				   - SIDEBAR_GAP_WIDTH * 2)
+			       : singleSidebarMaxWidth
+
   const tagPanel = (
       <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
 	<div className="mb-3 flex items-center justify-between gap-3">
@@ -797,30 +852,26 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	  {theatre && <title>{`${ theatreTitle } | ${ SITE_TITLE }`}</title>}
 	</Helmet>
 
-	<div className={cn (
+	<div
-	    'grid min-h-full gap-4 overflow-visible md:h-full md:overflow-hidden',
+	    ref={sidebarContainerRef}
-	    (layoutMode === 'threeColumns'
+	    data-sidebar-container
-	     && ['md:grid-cols-[16rem_minmax(0,1fr)_22rem]',
+	    className="flex min-h-full flex-col gap-4 overflow-visible md:h-full md:flex-row
-		 'xl:grid-cols-[18rem_minmax(0,1fr)_24rem]']),
+		       md:overflow-hidden">
-	    (layoutMode === 'tagsBottom'
-	     && 'md:grid-cols-[minmax(0,1fr)_22rem] xl:grid-cols-[minmax(0,1fr)_24rem]'),
-	    (layoutMode === 'commentsBottom'
-	     && 'md:grid-cols-[16rem_minmax(0,1fr)] xl:grid-cols-[18rem_minmax(0,1fr)]'))}>
 	  {layoutMode !== 'tagsBottom' && (
-	      <motion.aside
+	      <SidebarComponent
-		  layout="position"
+		  sidebarKey="theatre-tags"
-		  className="hidden min-w-0 space-y-4 md:order-none md:block md:overflow-y-auto
+		  side="left"
-			     md:[direction:rtl]">
+		  maxWidth={leftSidebarMaxWidth}
-		<div className="md:[direction:ltr]">
+		  onWidthChange={setLeftSidebarWidth}
-		  {tagPanel}
+		  className="hidden md:block">
-		</div>
+		{tagPanel}
-	      </motion.aside>)}
+	      </SidebarComponent>)}
 
 	  <motion.main
 	      layout="position"
-	      className={cn ('order-1 min-w-0 space-y-4 md:order-none md:overflow-y-auto',
+	      className="order-1 min-w-0 flex-1 space-y-4 md:order-none
-			     layoutMode === 'tagsBottom' && 'md:[direction:rtl]')}>
+			 md:min-w-[360px] md:overflow-y-auto">
-	    <div className={cn ('space-y-4', layoutMode === 'tagsBottom' && 'md:[direction:ltr]')}>
+	    <div className="space-y-4">
 	      <section className="overflow-hidden rounded border-zinc-300
 				  dark:border-zinc-800">
 		<div className="flex flex-wrap items-center justify-between gap-3
@@ -956,12 +1007,17 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	  </motion.main>
 
 	  {layoutMode !== 'commentsBottom' && (
-	      <motion.aside
+	      <SidebarComponent
-		  layout="position"
+		  sidebarKey="theatre-comments"
-		  className="hidden min-w-0 space-y-4 md:order-none md:block md:overflow-y-auto">
+		  side="right"
-		{commentsPanel}
+		  maxWidth={rightSidebarMaxWidth}
-		{participantsPanel}
+		  onWidthChange={setRightSidebarWidth}
-	      </motion.aside>)}
+		  className="hidden md:block">
+		<div className="space-y-4">
+		  {commentsPanel}
+		  {participantsPanel}
+		</div>
+	      </SidebarComponent>)}
 	</div>
       </motion.div>)
 }

frontend/src/pages/users/SettingPage.tsx

@@ -1,475 +1,43 @@
-import type {
+import type { FC } from 'react'
-    Dispatch,
-    FC,
-    KeyboardEvent,
-    SetStateAction,
-} from 'react'
 
-import { useCallback, useEffect, useMemo, useState } from 'react'
+import { useEffect, useState } from 'react'
 import { Helmet } from 'react-helmet-async'
-import { useLocation, useNavigate } from 'react-router-dom'
 
 import FieldError from '@/components/common/FieldError'
+import Form from '@/components/common/Form'
 import FormField from '@/components/common/FormField'
 import Label from '@/components/common/Label'
 import PageTitle from '@/components/common/PageTitle'
 import MainArea from '@/components/layout/MainArea'
-import { useUserSettings } from '@/components/users/UserSettingsProvider'
 import InheritDialogue from '@/components/users/InheritDialogue'
 import UserCodeDialogue from '@/components/users/UserCodeDialogue'
 import { Button } from '@/components/ui/button'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
 import { apiPut } from '@/lib/api'
-import {
+import { inputClass } from '@/lib/utils'
-    AUTO_FETCH_OPTIONS,
-    DEFAULT_USER_SETTINGS,
-    THEME_OPTIONS,
-    WIKI_EDITOR_MODE_OPTIONS,
-    updateUserSettings,
-} from '@/lib/settings'
-import { cn, inputClass } from '@/lib/utils'
 import { useValidationErrors } from '@/lib/useValidationErrors'
 
 import type { User } from '@/types'
-import type { UserSettings } from '@/lib/settings'
 
 type Props = { user:    User | null
-	       setUser: Dispatch<SetStateAction<User | null>> }
+	       setUser: React.Dispatch<React.SetStateAction<User | null>> }
 
 type UserFormField = 'name'
-type SettingsFormField =
-    | 'theme'
-    | 'autoFetchTitle'
-    | 'autoFetchThumbnail'
-    | 'wikiEditorMode'
-
-type SettingsTab = 'account' | 'theme' | 'keyboard' | 'editing' | 'wiki'
-
-type TabSpec = {
-    id:     SettingsTab
-    label:  string }
-
-type NameFieldErrors = Partial<Record<UserFormField, string[]>>
-type SettingsFieldErrors = Partial<Record<SettingsFormField, string[]>>
-
-type SharedSectionProps = {
-    draftSettings:         UserSettings
-    name:                  string
-    nameBaseErrors:        string[]
-    nameFieldErrors:       NameFieldErrors
-    onDraftSettingsChange: Dispatch<SetStateAction<UserSettings>>
-    onInheritOpen:         () => void
-    onNameChange:          (value: string) => void
-    onSettingsSubmit:      () => void
-    onUserCodeOpen:        () => void
-    onUserSubmit:          () => void
-    settingsBaseErrors:    string[]
-    settingsFieldErrors:   SettingsFieldErrors
-    user:                  User }
-
-const sectionClassName =
-    'space-y-4 rounded-xl border border-border bg-background/80 p-4'
-
-const desktopTabRailClassName = [
-    'hidden md:flex md:justify-center',
-].join (' ')
-
-const desktopTabRailInnerClassName = [
-    'grid w-fit grid-cols-[12rem_minmax(0,36rem)] items-start gap-6',
-].join (' ')
-
-const tabs: TabSpec[] = [
-    { id: 'account', label: 'アカウント' },
-    { id: 'theme', label: 'テーマ' },
-    { id: 'keyboard', label: 'キーボード' },
-    { id: 'editing', label: '編輯支援' },
-    { id: 'wiki', label: 'Wiki' },
-]
-
-const settingsTabByField: Record<SettingsFormField, SettingsTab> = {
-    theme:               'theme',
-    autoFetchTitle:      'editing',
-    autoFetchThumbnail:  'editing',
-    wikiEditorMode:      'wiki',
-}
-
-const settingsFieldOrder: SettingsFormField[] = [
-    'theme',
-    'autoFetchTitle',
-    'autoFetchThumbnail',
-    'wikiEditorMode',
-]
-
-const themeLabel: Record<UserSettings['theme'], string> = {
-    system: 'システム設定に従う',
-    light:  'ライト・モード',
-    dark:   'ダーク・モード',
-}
-
-const autoFetchLabel: Record<UserSettings['autoFetchTitle'], string> = {
-    auto:   '自動',
-    manual: '手動',
-    off:    '無効',
-}
-
-const wikiEditorModeLabel: Record<UserSettings['wikiEditorMode'], string> = {
-    split:   '左右表示',
-    write:   '本文のみ',
-    preview: 'プレビューのみ',
-}
-
-const keyboardShortcutRows = [
-    { action: '投稿詳細を開く', key: 'Enter', scope: '一覧・検索結果', conflict: 'なし' },
-    { action: '候補タグを選ぶ', key: '↑ / ↓ / Enter', scope: 'タグ入力', conflict: 'なし' },
-    { action: '候補タグを閉ぢる', key: 'Escape', scope: 'タグ入力', conflict: 'なし' },
-]
-
-const themeColorTargets = [
-    '背景色',
-    '文字色',
-    '枠線色',
-    'リンク色',
-    '強調色',
-    '通常タグ',
-    'キャラタグ',
-    '素材タグ',
-    'Nico タグ',
-    '廃止タグ',
-    'Wiki ありタグ',
-    'Wiki 未作成タグ',
-    '選択中タグ',
-    'ホバー中タグ',
-]
-
-
-const parseTab = (search: string): SettingsTab => {
-  const tab = new URLSearchParams (search).get ('tab')
-  return tabs.some (candidate => candidate.id === tab)
-    ? tab as SettingsTab
-    : 'account'
-}
-
-
-const tabButtonId = (tab: SettingsTab): string => `settings-tab-${ tab }`
-const tabPanelId = (tab: SettingsTab): string => `settings-panel-${ tab }`
-
-
-const AccountSection: FC<SharedSectionProps> = ({
-    name,
-    nameBaseErrors,
-    nameFieldErrors,
-    onInheritOpen,
-    onNameChange,
-    onUserCodeOpen,
-    onUserSubmit,
-    user,
-}) => (
-    <section className={sectionClassName}>
-      <h2 className="text-xl font-bold">アカウント</h2>
-      <FieldError messages={nameBaseErrors}/>
-
-      <FormField label="表示名" messages={nameFieldErrors.name}>
-	{({ describedBy, invalid }) => (
-	    <>
-	      <input
-		  type="text"
-		  aria-describedby={describedBy}
-		  aria-invalid={invalid}
-		  className={inputClass (invalid)}
-		  value={name}
-		  placeholder="名もなきニジラー"
-		  onChange={ev => onNameChange (ev.target.value)}/>
-	      {!(user.name) && (
-		  <p className="mt-1 text-sm text-red-500">
-		    名前が未設定のアカウントは 30 日間アクセスしないと削除されます!!!!
-		  </p>)}
-	    </>)}
-      </FormField>
-
-      <div className="flex flex-wrap gap-2">
-	<Button type="button" onClick={onUserSubmit}>
-	  表示名を更新
-	</Button>
-      </div>
-
-      <div className="space-y-2">
-	<Label>引継ぎ</Label>
-	<div className="flex flex-wrap gap-2">
-	  <Button
-	      type="button"
-	      onClick={onUserCodeOpen}
-	      className="bg-gray-600 text-white"
-	      disabled={!(user)}>
-	    引継ぎコードを表示
-	  </Button>
-	  <Button
-	      type="button"
-	      onClick={onInheritOpen}
-	      className="bg-red-600 text-white"
-	      disabled={!(user)}>
-	    ほかのブラウザから引継ぐ
-	  </Button>
-	</div>
-      </div>
-    </section>)
-
-
-const ThemeSection: FC<SharedSectionProps> = ({
-    draftSettings,
-    onDraftSettingsChange,
-    onSettingsSubmit,
-    settingsBaseErrors,
-    settingsFieldErrors,
-}) => (
-    <section className={sectionClassName}>
-      <h2 className="text-xl font-bold">テーマ</h2>
-      <FieldError messages={settingsBaseErrors}/>
-
-      <FormField label="基本テーマ" messages={settingsFieldErrors.theme}>
-	{() => (
-	    <select
-		className={inputClass (Boolean (settingsFieldErrors.theme?.length))}
-		value={draftSettings.theme}
-		onChange={ev => onDraftSettingsChange (current => ({
-		    ...current,
-		    theme: ev.target.value as UserSettings['theme'],
-		}))}>
-	      {THEME_OPTIONS.map (value => (
-		  <option key={value} value={value}>
-		    {themeLabel[value]}
-		  </option>))}
-	    </select>)}
-      </FormField>
-
-      <div className="space-y-2 rounded-lg border border-border/70 bg-muted/30 p-3 text-sm">
-	<p className="font-medium">今後の拡張予定</p>
-	<p>
-	  将来は `themes` または `user_themes` を導入し，ユーザごとの
-	  カスタム・テーマを持てる構造にする前提です．
-	</p>
-	<p>その際は次の色を個別に設定できるようにします．</p>
-	<div className="flex flex-wrap gap-2">
-	  {themeColorTargets.map (target => (
-	      <span
-		  key={target}
-		  className="rounded-full border border-border/70 px-2 py-1">
-		{target}
-	      </span>))}
-	</div>
-      </div>
-
-      <Button type="button" onClick={onSettingsSubmit}>
-	設定を保存
-      </Button>
-    </section>)
-
-
-const KeyboardSection: FC = () => (
-    <section className={sectionClassName}>
-      <h2 className="text-xl font-bold">キーボード</h2>
-
-      <div className="space-y-2 rounded-lg border border-border/70 bg-muted/30 p-3 text-sm">
-	<p>
-	  初期実装では固定ショートカット一覧のみを表示します．
-	  将来は `action / key / scope / conflict` を持つ
-	  key bind 設定へ拡張する前提です．
-	</p>
-      </div>
-
-      <div className="overflow-x-auto">
-	<table className="w-full min-w-[28rem] table-fixed border-collapse text-sm">
-	  <thead className="border-b border-border">
-	    <tr>
-	      <th className="p-2 text-left">操作</th>
-	      <th className="p-2 text-left">キー</th>
-	      <th className="p-2 text-left">適用範囲</th>
-	      <th className="p-2 text-left">競合</th>
-	    </tr>
-	  </thead>
-	  <tbody>
-	    {keyboardShortcutRows.map (row => (
-		<tr key={row.action} className="border-b border-border/60 last:border-b-0">
-		  <td className="p-2">{row.action}</td>
-		  <td className="p-2 font-mono">{row.key}</td>
-		  <td className="p-2">{row.scope}</td>
-		  <td className="p-2">{row.conflict}</td>
-		</tr>))}
-	  </tbody>
-	</table>
-      </div>
-    </section>)
-
-
-const EditingSection: FC<SharedSectionProps> = ({
-    draftSettings,
-    onDraftSettingsChange,
-    onSettingsSubmit,
-    settingsBaseErrors,
-    settingsFieldErrors,
-}) => (
-    <section className={sectionClassName}>
-      <h2 className="text-xl font-bold">編輯支援</h2>
-      <FieldError messages={settingsBaseErrors}/>
-
-      <FormField label="タイトル自動取得" messages={settingsFieldErrors.autoFetchTitle}>
-	{() => (
-	    <select
-		className={inputClass (
-		    Boolean (settingsFieldErrors.autoFetchTitle?.length),
-		)}
-		value={draftSettings.autoFetchTitle}
-		onChange={ev => onDraftSettingsChange (current => ({
-		    ...current,
-		    autoFetchTitle: ev.target.value as UserSettings['autoFetchTitle'],
-		}))}>
-	      {AUTO_FETCH_OPTIONS.map (value => (
-		  <option key={value} value={value}>
-		    {autoFetchLabel[value]}
-		  </option>))}
-	    </select>)}
-      </FormField>
-
-      <FormField
-	  label="サムネール自動取得"
-	  messages={settingsFieldErrors.autoFetchThumbnail}>
-	{() => (
-	    <select
-		className={inputClass (
-		    Boolean (settingsFieldErrors.autoFetchThumbnail?.length),
-		)}
-		value={draftSettings.autoFetchThumbnail}
-		onChange={ev => onDraftSettingsChange (current => ({
-		    ...current,
-		    autoFetchThumbnail:
-			ev.target.value as UserSettings['autoFetchThumbnail'],
-		}))}>
-	      {AUTO_FETCH_OPTIONS.map (value => (
-		  <option key={value} value={value}>
-		    {autoFetchLabel[value]}
-		  </option>))}
-	    </select>)}
-      </FormField>
-
-      <Button type="button" onClick={onSettingsSubmit}>
-	設定を保存
-      </Button>
-    </section>)
-
-
-const WikiSection: FC<SharedSectionProps> = ({
-    draftSettings,
-    onDraftSettingsChange,
-    onSettingsSubmit,
-    settingsBaseErrors,
-    settingsFieldErrors,
-}) => (
-    <section className={sectionClassName}>
-      <h2 className="text-xl font-bold">Wiki</h2>
-      <FieldError messages={settingsBaseErrors}/>
-
-      <FormField label="エディタ表示" messages={settingsFieldErrors.wikiEditorMode}>
-	{() => (
-	    <select
-		className={inputClass (
-		    Boolean (settingsFieldErrors.wikiEditorMode?.length),
-		)}
-		value={draftSettings.wikiEditorMode}
-		onChange={ev => onDraftSettingsChange (current => ({
-		    ...current,
-		    wikiEditorMode: ev.target.value as UserSettings['wikiEditorMode'],
-		}))}>
-	      {WIKI_EDITOR_MODE_OPTIONS.map (value => (
-		  <option key={value} value={value}>
-		    {wikiEditorModeLabel[value]}
-		  </option>))}
-	    </select>)}
-      </FormField>
-
-      <Button type="button" onClick={onSettingsSubmit}>
-	設定を保存
-      </Button>
-    </section>)
 
 
 const SettingPage: FC<Props> = ({ user, setUser }) => {
-  const location = useLocation ()
-  const navigate = useNavigate ()
-
-  const [draftSettings, setDraftSettings] = useState<UserSettings> (DEFAULT_USER_SETTINGS)
   const [name, setName] = useState ('')
   const [userCodeVsbl, setUserCodeVsbl] = useState (false)
   const [inheritVsbl, setInheritVsbl] = useState (false)
-  const { error, loaded, settings, setSettings } = useUserSettings ()
+  const { baseErrors, fieldErrors, clearValidationErrors, applyValidationError } =
-  const {
+      useValidationErrors<UserFormField> ()
-    baseErrors: nameBaseErrors,
-    fieldErrors: nameFieldErrors,
-    clearValidationErrors: clearNameValidationErrors,
-    applyValidationError: applyNameValidationError,
-  } = useValidationErrors<UserFormField> ()
-  const {
-    baseErrors: settingsBaseErrors,
-    fieldErrors: settingsFieldErrors,
-    clearValidationErrors: clearSettingsValidationErrors,
-    applyValidationError: applySettingsValidationError,
-  } = useValidationErrors<SettingsFormField> ()
 
-  const activeTab = useMemo<SettingsTab> (() => parseTab (location.search), [location.search])
+  const handleSubmit = async () => {
-
-  const setActiveTab = useCallback ((tab: SettingsTab) => {
-    const params = new URLSearchParams (location.search)
-    params.set ('tab', tab)
-    navigate (
-	`${ location.pathname }${ params.toString () ? `?${ params.toString () }` : '' }`,
-	{ replace: true },
-    )
-  }, [location.pathname, location.search, navigate])
-
-  const settingsTabErrors = useMemo<Record<SettingsTab, boolean>> (() => ({
-      account: Boolean (nameFieldErrors.name?.length),
-      theme: Boolean (settingsFieldErrors.theme?.length),
-      keyboard: false,
-      editing: (
-	  Boolean (settingsFieldErrors.autoFetchTitle?.length)
-	  || Boolean (settingsFieldErrors.autoFetchThumbnail?.length)
-      ),
-      wiki: Boolean (settingsFieldErrors.wikiEditorMode?.length),
-  }), [nameFieldErrors.name, settingsFieldErrors])
-
-  const handleTabKeyDown = (event: KeyboardEvent<HTMLButtonElement>) => {
-    const currentIndex = tabs.findIndex (tab => tab.id === activeTab)
-
-    switch (event.key)
-    {
-    case 'ArrowRight':
-    case 'ArrowDown':
-      event.preventDefault ()
-      setActiveTab (tabs[(currentIndex + 1) % tabs.length].id)
-      break
-
-    case 'ArrowLeft':
-    case 'ArrowUp':
-      event.preventDefault ()
-      setActiveTab (tabs[(currentIndex - 1 + tabs.length) % tabs.length].id)
-      break
-
-    case 'Home':
-      event.preventDefault ()
-      setActiveTab (tabs[0].id)
-      break
-
-    case 'End':
-      event.preventDefault ()
-      setActiveTab (tabs[tabs.length - 1].id)
-      break
-    }
-  }
-
-  const handleUserSubmit = async () => {
     if (!(user))
       return
 
-    clearNameValidationErrors ()
+    clearValidationErrors ()
 
     const formData = new FormData
     formData.append ('name', name)
@@ -479,35 +47,13 @@ const SettingPage: FC<Props> = ({ user, setUser }) => {
       const data = await apiPut<User> (
 	  `/users/${ user.id }`, formData,
 	  { headers: { 'Content-Type': 'multipart/form-data' } })
-      setUser (currentUser => ({ ...currentUser, ...data }))
+      setUser (user => ({ ...user, ...data }))
-      toast ({ title: '表示名を更新しました．' })
+      toast ({ title: '設定を更新しました．' })
     }
-    catch (submitError)
+    catch (e)
     {
-      applyNameValidationError (submitError)
+      applyValidationError (e)
-      toast ({ title: '表示名を更新できませんでした．' })
+      toast ({ title: 'しっぱい……' })
-    }
-  }
-
-  const handleSettingsSubmit = async () => {
-    clearSettingsValidationErrors ()
-
-    try
-    {
-      const data = await updateUserSettings ({
-	  theme: draftSettings.theme,
-	  auto_fetch_title: draftSettings.autoFetchTitle,
-	  auto_fetch_thumbnail: draftSettings.autoFetchThumbnail,
-	  wiki_editor_mode: draftSettings.wikiEditorMode,
-      })
-      setDraftSettings (data)
-      setSettings (data)
-      toast ({ title: '設定を保存しました．' })
-    }
-    catch (submitError)
-    {
-      applySettingsValidationError (submitError)
-      toast ({ title: '設定を保存できませんでした．' })
     }
   }
 
@@ -518,39 +64,6 @@ const SettingPage: FC<Props> = ({ user, setUser }) => {
     setName (user.name ?? '')
   }, [user])
 
-  useEffect (() => {
-    setDraftSettings (settings)
-  }, [settings])
-
-  useEffect (() => {
-    if (nameFieldErrors.name?.length)
-      setActiveTab ('account')
-  }, [nameFieldErrors.name, setActiveTab])
-
-  useEffect (() => {
-    const fieldWithError = settingsFieldOrder.find (
-	field => (settingsFieldErrors[field]?.length ?? 0) > 0,
-    )
-    if (fieldWithError)
-      setActiveTab (settingsTabByField[fieldWithError])
-  }, [setActiveTab, settingsFieldErrors])
-
-  const sectionProps: SharedSectionProps | null = user ? {
-      draftSettings,
-      name,
-      nameBaseErrors,
-      nameFieldErrors,
-      onDraftSettingsChange: setDraftSettings,
-      onInheritOpen: () => setInheritVsbl (true),
-      onNameChange: setName,
-      onSettingsSubmit: handleSettingsSubmit,
-      onUserCodeOpen: () => setUserCodeVsbl (true),
-      onUserSubmit: handleUserSubmit,
-      settingsBaseErrors,
-      settingsFieldErrors,
-      user,
-  } : null
-
   return (
       <MainArea>
 	<Helmet>
@@ -558,84 +71,62 @@ const SettingPage: FC<Props> = ({ user, setUser }) => {
 	  <title>設定 | {SITE_TITLE}</title>
 	</Helmet>
 
-	<div className="space-y-4 p-4">
+	<Form>
-	  <div className="mx-auto max-w-xl space-y-4">
+	  <PageTitle>設定</PageTitle>
-	    <PageTitle>設定</PageTitle>
-	    <FieldError messages={error ? [error] : []}/>
-	  </div>
 
-	  {user && loaded ? (
+	  {user ? (
 	      <>
-		<div className="mx-auto max-w-xl space-y-6 md:hidden">
+		<FieldError messages={baseErrors}/>
-		  {sectionProps && (
+
+		{/* 名前 */}
+		<FormField label="表示名" messages={fieldErrors.name}>
+		  {({ describedBy, invalid }) => (
 		      <>
-			<AccountSection {...sectionProps}/>
+		  <input type="text"
-			<ThemeSection {...sectionProps}/>
+			 aria-describedby={describedBy}
-			<KeyboardSection/>
+			 aria-invalid={invalid}
-			<EditingSection {...sectionProps}/>
+			 className={inputClass (invalid)}
-			<WikiSection {...sectionProps}/>
+			 value={name}
+			 placeholder="名もなきニジラー"
+			 onChange={ev => setName (ev.target.value)}/>
+		  {(user && !(user.name)) && (
+		      <p className="mt-1 text-sm text-red-500">
+			名前が未設定のアカウントは 30 日間アクセスしないと削除されます!!!!
+		      </p>)}
 		      </>)}
-		</div>
+		</FormField>
 
-		<div className={desktopTabRailClassName}>
+		{/* 送信 */}
-		  <div className={desktopTabRailInnerClassName}>
+		<Button onClick={handleSubmit}
-		    <div
+			className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
-			role="tablist"
+		  更新
-			aria-label="設定区分"
+		</Button>
-			aria-orientation="vertical"
-			className="sticky top-4 flex h-fit flex-col gap-2">
-		      {tabs.map (tab => (
-			  <button
-			      key={tab.id}
-			      id={tabButtonId (tab.id)}
-			      type="button"
-			      role="tab"
-			      aria-selected={activeTab === tab.id}
-			      aria-controls={tabPanelId (tab.id)}
-			      tabIndex={activeTab === tab.id ? 0 : -1}
-			      className={cn (
-				  'rounded-xl border px-4 py-3 text-left text-sm font-medium',
-				  activeTab === tab.id
-				  ? ['border-slate-900 bg-slate-900 text-white',
-				     'dark:border-slate-100 dark:bg-slate-100 dark:text-slate-900']
-				  : ['border-slate-300 bg-white text-slate-700',
-				     'dark:border-slate-700 dark:bg-slate-900 dark:text-slate-100'],
-			      )}
-			      onClick={() => setActiveTab (tab.id)}
-			      onKeyDown={handleTabKeyDown}>
-			    {tab.label}
-			    {settingsTabErrors[tab.id] ? ' ⚠' : ''}
-			  </button>))}
-		    </div>
 
-		    <div className="w-[36rem] max-w-full">
+		{/* 引継ぎ */}
-		      {sectionProps && (
+		<div>
-			  <div
+		  <Label>引継ぎ</Label>
-			      id={tabPanelId (activeTab)}
+		  <Button onClick={() => setUserCodeVsbl (true)}
-			      role="tabpanel"
+			  className="px-4 py-2 bg-gray-600 text-white rounded disabled:bg-gray-400"
-			      aria-labelledby={tabButtonId (activeTab)}>
+			  disabled={!(user)}>
-			    {activeTab === 'account' && <AccountSection {...sectionProps}/>}
+		    引継ぎコードを表示
-			    {activeTab === 'theme' && <ThemeSection {...sectionProps}/>}
+		  </Button>
-			    {activeTab === 'keyboard' && <KeyboardSection/>}
+		  <Button onClick={() => setInheritVsbl (true)}
-			    {activeTab === 'editing' && <EditingSection {...sectionProps}/>}
+			  className="ml-2 px-4 py-2 bg-red-600 text-white rounded disabled:bg-gray-400"
-			    {activeTab === 'wiki' && <WikiSection {...sectionProps}/>}
+			  disabled={!(user)}>
-			  </div>)}
+		    ほかのブラウザから引継ぐ
-		    </div>
+		  </Button>
-		  </div>
 		</div>
 	      </>) : 'Loading...'}
-	</div>
+	</Form>
 
-	<UserCodeDialogue
+	<UserCodeDialogue visible={userCodeVsbl}
-	    visible={userCodeVsbl}
+			  onVisibleChange={setUserCodeVsbl}
-	    onVisibleChange={setUserCodeVsbl}
+			  user={user}
-	    user={user}
+			  setUser={setUser}/>
-	    setUser={setUser}/>
 
-	<InheritDialogue
+	<InheritDialogue visible={inheritVsbl}
-	    visible={inheritVsbl}
+			 onVisibleChange={setInheritVsbl}
-	    onVisibleChange={setInheritVsbl}
+			 setUser={setUser}/>
-	    setUser={setUser}/>
       </MainArea>)
 }
 

frontend/src/pages/wiki/WikiEditPage.tsx

@@ -8,7 +8,6 @@ import { useParams, useNavigate } from 'react-router-dom'
 import FieldError from '@/components/common/FieldError'
 import FormField from '@/components/common/FormField'
 import MainArea from '@/components/layout/MainArea'
-import { useUserSettings } from '@/components/users/UserSettingsProvider'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
 import { apiGet, apiPut } from '@/lib/api'
@@ -26,27 +25,6 @@ import type { User, WikiPage } from '@/types'
 
 const mdParser = new MarkdownIt
 
-type EditorView = {
-    menu:  boolean
-    md:    boolean
-    html:  boolean }
-
-const editorView = (
-    mode: 'split' | 'write' | 'preview',
-): EditorView => {
-  switch (mode)
-  {
-  case 'write':
-    return { menu: true, md: true, html: false }
-
-  case 'preview':
-    return { menu: true, md: false, html: true }
-
-  default:
-    return { menu: true, md: true, html: true }
-  }
-}
-
 type Props = { user: User | null }
 
 type WikiFormField = 'title' | 'body'
@@ -54,7 +32,6 @@ type WikiFormField = 'title' | 'body'
 
 const WikiEditPage: FC<Props> = ({ user }) => {
   const editable = canEditContent (user)
-  const { settings } = useUserSettings ()
 
   const { id } = useParams ()
 
@@ -137,7 +114,6 @@ const WikiEditPage: FC<Props> = ({ user }) => {
 		  {() => (
 		      <MdEditor value={body}
 				style={{ height: '500px' }}
-				config={{ view: editorView (settings.wikiEditorMode) }}
 				renderHTML={text => mdParser.render (text)}
 				onChange={({ text }) => setBody (text)}/>)}
 		</FormField>

frontend/src/pages/wiki/WikiNewPage.tsx

@@ -9,7 +9,6 @@ import { useLocation, useNavigate } from 'react-router-dom'
 import FieldError from '@/components/common/FieldError'
 import FormField from '@/components/common/FormField'
 import MainArea from '@/components/layout/MainArea'
-import { useUserSettings } from '@/components/users/UserSettingsProvider'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
 import { apiPost } from '@/lib/api'
@@ -24,27 +23,6 @@ import type { User, WikiPage } from '@/types'
 
 const mdParser = new MarkdownIt
 
-type EditorView = {
-    menu:  boolean
-    md:    boolean
-    html:  boolean }
-
-const editorView = (
-    mode: 'split' | 'write' | 'preview',
-): EditorView => {
-  switch (mode)
-  {
-  case 'write':
-    return { menu: true, md: true, html: false }
-
-  case 'preview':
-    return { menu: true, md: false, html: true }
-
-  default:
-    return { menu: true, md: true, html: true }
-  }
-}
-
 type Props = { user: User | null }
 
 type WikiFormField = 'title' | 'body'
@@ -52,7 +30,6 @@ type WikiFormField = 'title' | 'body'
 
 const WikiNewPage: FC<Props> = ({ user }) => {
   const editable = canEditContent (user)
-  const { settings } = useUserSettings ()
 
   const location = useLocation ()
   const navigate = useNavigate ()
@@ -115,7 +92,6 @@ const WikiNewPage: FC<Props> = ({ user }) => {
 	    {() => (
 		<MdEditor value={body}
 			  style={{ height: '500px' }}
-			  config={{ view: editorView (settings.wikiEditorMode) }}
 			  renderHTML={text => mdParser.render (text)}
 			  onChange={({ text }) => setBody (text)}/>)}
 	  </FormField>