diff --git a/src/preload/index.ts b/src/preload/index.ts
index 3f51913..4e7a688 100644
--- a/src/preload/index.ts
+++ b/src/preload/index.ts
@@ -106,7 +106,7 @@ const api: AppApi = {
     ipcRenderer.send(Ipc.HOSTKEY_RESPOND, promptId, action),
 
   getSettings: () => ipcRenderer.invoke(Ipc.SETTINGS_GET),
-  saveSettings: (next: AppSettings) => ipcRenderer.invoke(Ipc.SETTINGS_SET, next),
+  saveSettings: (next: Partial<AppSettings>) => ipcRenderer.invoke(Ipc.SETTINGS_SET, next),
   onSettingsChanged: (cb: (s: AppSettings) => void) => {
     const listener = (_: unknown, s: AppSettings): void => cb(s)
     ipcRenderer.on(Ipc.SETTINGS_CHANGED, listener)
@@ -121,6 +121,7 @@ const api: AppApi = {
   deleteLayout: (id: string) => ipcRenderer.invoke(Ipc.LAYOUTS_DELETE, id),
 
   updateCheck: () => ipcRenderer.invoke(Ipc.UPDATE_CHECK),
+  getUpdateState: () => ipcRenderer.invoke(Ipc.UPDATE_STATE_GET),
   updateDownload: () => ipcRenderer.invoke(Ipc.UPDATE_DOWNLOAD),
   updateInstall: () => ipcRenderer.invoke(Ipc.UPDATE_INSTALL),
   updateChangelog: () => ipcRenderer.invoke(Ipc.UPDATE_CHANGELOG),
diff --git a/src/shared/api.ts b/src/shared/api.ts
index b6216d1..31ce523 100644
--- a/src/shared/api.ts
+++ b/src/shared/api.ts
@@ -97,7 +97,7 @@ export interface AppApi {
 
   // ---- settings ----
   getSettings(): Promise<AppSettings>
-  saveSettings(next: AppSettings): Promise<AppSettings>
+  saveSettings(next: Partial<AppSettings>): Promise<AppSettings>
   onSettingsChanged(cb: (s: AppSettings) => void): () => void
 
   // ---- fonts ----
@@ -112,6 +112,8 @@ export interface AppApi {
 
   // ---- updater (domestic feed first, GitHub fallback) ----
   updateCheck(): Promise<UpdateState>
+  /** read the updater's current state without triggering a network check */
+  getUpdateState(): Promise<UpdateState>
   updateDownload(): Promise<void>
   updateInstall(): Promise<void>
   updateChangelog(): Promise<ReleaseNote[]>
diff --git a/src/shared/i18n/dicts/en/main.ts b/src/shared/i18n/dicts/en/main.ts
index bf0ea24..2ec71b8 100644
--- a/src/shared/i18n/dicts/en/main.ts
+++ b/src/shared/i18n/dicts/en/main.ts
@@ -13,7 +13,7 @@ const main: Record<string, string> = {
   'main.tray.closeDetail': 'Minimizing to tray keeps your terminal sessions running.',
   'main.tray.rememberChoice': 'Remember my choice, never ask again',
 
-  'main.updater.feedFailed': 'Domestic feed: {gitea}; GitHub: {github}',
+  'main.updater.feedFailed': 'Gitea feed: {gitea}; GitHub: {github}',
 
   'main.ssh.connectTimeout': 'Connection timed out ({host}:{port})',
   'main.ssh.saveFingerprintFailed': 'Failed to save the host fingerprint: {detail}',
@@ -27,6 +27,7 @@ const main: Record<string, string> = {
   'main.sftp.deleteFailed': 'Delete failed: {detail}',
   'main.sftp.invalidMode': 'Invalid permission value: {mode}',
   'main.sftp.invalidUidGid': 'Invalid uid/gid',
+  'main.sftp.commandTimeout': 'Command timed out',
   'main.sftp.commandExitCode': 'Command exited with code {code}',
   'main.sftp.cancelled': 'Cancelled',
 
@@ -47,6 +48,7 @@ const main: Record<string, string> = {
 
   'main.sysinfo.sessionGone': 'SSH session is missing or disconnected',
   'main.sysinfo.execFailed': 'SSH exec failed',
+  'main.sysinfo.pollTimeout': 'Monitoring command timed out',
   'main.sysinfo.parseFailed': 'Parse failed: {message}',
   'main.pty.serviceNotReady': 'SSH session service is not initialised yet',
   'main.pty.missingConnectionId': 'SSH session is missing its connectionId',
diff --git a/src/shared/i18n/dicts/en/settings.ts b/src/shared/i18n/dicts/en/settings.ts
index cdbd6ba..d10f80d 100644
--- a/src/shared/i18n/dicts/en/settings.ts
+++ b/src/shared/i18n/dicts/en/settings.ts
@@ -98,6 +98,11 @@ const settings: Record<string, string> = {
     'Together with the global key this shows or hides the window from anywhere; if registration fails (a conflict with another app) it simply has no effect and the app reports no error.',
   'settings.system.shortcutRecording': 'Press the keys…',
   'settings.system.shortcutPlaceholder': 'Click and press a shortcut, leave empty to disable',
+  'settings.system.shortcutConflict':
+    'This shortcut is already used by the app (Ctrl+= / Ctrl+- / Ctrl+0 / Ctrl+PgUp / Ctrl+PgDn). Please choose another.',
+  'settings.resetTerminal': 'Reset terminal settings',
+  'settings.resetTerminalTitle': 'Reset terminal settings?',
+  'settings.resetTerminalDesc': 'All terminal settings — font, cursor, rendering and theme — will be restored to defaults.',
   'settings.highlight.alert':
     'Custom highlighting improves readability at a small performance cost. Rules are applied in priority order. PS: colors are injected as text is written to the terminal, so existing scrollback is unaffected',
   'settings.highlight.enabled': 'Enabled',
@@ -121,6 +126,17 @@ const settings: Record<string, string> = {
   'settings.highlight.resetOk': 'Restore',
   'settings.highlight.createTitle': 'New highlight rule',
   'settings.highlight.editTitle': 'Edit highlight rule',
+  'settings.highlight.builtin.perm': 'Linux permissions and user/group',
+  'settings.highlight.builtin.path': 'Linux file paths',
+  'settings.highlight.builtin.shellkw': 'Shell keywords and control flow',
+  'settings.highlight.builtin.okstate': 'Success states',
+  'settings.highlight.builtin.badstate': 'Error/warning states',
+  'settings.highlight.builtin.quoted': 'Strings and quotes',
+  'settings.highlight.builtin.envvar': 'Environment variables and arguments',
+  'settings.highlight.builtin.ipv4': 'Network and IP addresses',
+  'settings.highlight.builtin.datetime': 'Time and date',
+  'settings.highlight.builtin.numbers': 'Numbers and counts',
+  'settings.highlight.builtin.url': 'Web links',
   'settings.theme.accent': 'Tab accent color',
   'settings.theme.accentDesc': 'Accent color for the active tab border, the sidebar indicator, and SSH badges',
   'settings.theme.customBadge': 'Custom',
diff --git a/src/shared/i18n/dicts/en/ssh.ts b/src/shared/i18n/dicts/en/ssh.ts
index 23d9b71..6282681 100644
--- a/src/shared/i18n/dicts/en/ssh.ts
+++ b/src/shared/i18n/dicts/en/ssh.ts
@@ -13,7 +13,7 @@ const ssh: Record<string, string> = {
   'ssh.fields.askPasswordHint':
     'Prompts for the password on every connection instead of using the saved one',
   'ssh.fields.passwordPlaceholder': 'Leave empty to keep the saved password',
-  'ssh.fields.keyPath': 'Private key path (path on the server, optional)',
+  'ssh.fields.keyPath': 'Private key file path (on this computer, optional)',
   'ssh.fields.keyContent': 'Private key content',
   'ssh.fields.keyContentPlaceholder':
     'Paste the private key; leave empty to use the path above (leave empty while editing to keep the saved key)',
@@ -100,6 +100,8 @@ const ssh: Record<string, string> = {
   'ssh.file.up': 'Parent folder',
   'ssh.file.refresh': 'Refresh',
   'ssh.file.uploadFile': 'Upload files',
+  'ssh.file.overwriteTitle': 'Overwrite existing file?',
+  'ssh.file.overwriteDesc': 'A file with the same name exists in the target directory; uploading will overwrite its contents.',
   'ssh.file.downloadSelected': 'Download selection',
   'ssh.file.permOwner': 'Permissions / owner',
   'ssh.file.open': 'Open',
diff --git a/src/shared/i18n/dicts/ja/main.ts b/src/shared/i18n/dicts/ja/main.ts
index 311f807..e49df22 100644
--- a/src/shared/i18n/dicts/ja/main.ts
+++ b/src/shared/i18n/dicts/ja/main.ts
@@ -13,7 +13,7 @@ const main: Record<string, string> = {
   'main.tray.closeDetail': 'トレイに最小化すると、ターミナルセッションは実行を続けます。',
   'main.tray.rememberChoice': '選択を記憶して今後確認しない',
 
-  'main.updater.feedFailed': '国内フィード: {gitea}；GitHub: {github}',
+  'main.updater.feedFailed': 'Gitea フィード: {gitea}；GitHub: {github}',
 
   'main.ssh.connectTimeout': '接続がタイムアウトしました ({host}:{port})',
   'main.ssh.saveFingerprintFailed': 'ホスト鍵のフィンガープリントを保存できませんでした: {detail}',
@@ -27,6 +27,7 @@ const main: Record<string, string> = {
   'main.sftp.deleteFailed': '削除に失敗しました: {detail}',
   'main.sftp.invalidMode': '不正なパーミッション値: {mode}',
   'main.sftp.invalidUidGid': '不正な uid/gid',
+  'main.sftp.commandTimeout': 'コマンドがタイムアウトしました',
   'main.sftp.commandExitCode': 'コマンドの終了コード {code}',
   'main.sftp.cancelled': 'キャンセルしました',
 
@@ -47,6 +48,7 @@ const main: Record<string, string> = {
 
   'main.sysinfo.sessionGone': 'SSH セッションが存在しないか切断されています',
   'main.sysinfo.execFailed': 'SSH exec に失敗しました',
+  'main.sysinfo.pollTimeout': '監視コマンドがタイムアウトしました',
   'main.sysinfo.parseFailed': '解析に失敗しました: {message}',
   'main.pty.serviceNotReady': 'SSH セッションサービスが未初期化です',
   'main.pty.missingConnectionId': 'SSH セッションに connectionId がありません',
diff --git a/src/shared/i18n/dicts/ja/settings.ts b/src/shared/i18n/dicts/ja/settings.ts
index a8bd2a4..879ed64 100644
--- a/src/shared/i18n/dicts/ja/settings.ts
+++ b/src/shared/i18n/dicts/ja/settings.ts
@@ -95,6 +95,11 @@ const settings: Record<string, string> = {
     'グローバルキーと組み合わせると、どの画面からでもウィンドウを呼び出し／非表示にできます。登録に失敗した場合（他のソフトとの競合）は効果がなく、アプリにエラーは表示されません。',
   'settings.system.shortcutRecording': 'キーを押してください…',
   'settings.system.shortcutPlaceholder': 'クリックしてショートカットを押す。空欄で無効',
+  'settings.system.shortcutConflict':
+    'このショートカットはアプリ内で既に使用されています（Ctrl+= / Ctrl+- / Ctrl+0 / Ctrl+PgUp / Ctrl+PgDn）。別のものを選んでください。',
+  'settings.resetTerminal': 'ターミナル設定をリセット',
+  'settings.resetTerminalTitle': 'ターミナル設定をリセットしますか？',
+  'settings.resetTerminalDesc': 'フォント、カーソル、レンダリング、テーマなどすべてのターミナル設定がデフォルトに戻ります。',
   'settings.highlight.alert':
     '独自のハイライトは見やすさを高めますが、わずかに性能を消費します。ルールは優先順に適用されます。PS: ハイライトはターミナルへの書き込み時に色を注入するため、既存のスクロールバックには反映されません',
   'settings.highlight.enabled': '有効',
@@ -118,6 +123,17 @@ const settings: Record<string, string> = {
   'settings.highlight.resetOk': '元に戻す',
   'settings.highlight.createTitle': 'ハイライトルールを作成',
   'settings.highlight.editTitle': 'ハイライトルールを編集',
+  'settings.highlight.builtin.perm': 'Linux のパーミッションとユーザー',
+  'settings.highlight.builtin.path': 'Linux のファイルパス',
+  'settings.highlight.builtin.shellkw': 'Shell のキーワードと制御構文',
+  'settings.highlight.builtin.okstate': '成功ステータス',
+  'settings.highlight.builtin.badstate': 'エラー・警告ステータス',
+  'settings.highlight.builtin.quoted': '文字列と引用符',
+  'settings.highlight.builtin.envvar': '環境変数と引数',
+  'settings.highlight.builtin.ipv4': 'ネットワークと IP アドレス',
+  'settings.highlight.builtin.datetime': '時刻と日付',
+  'settings.highlight.builtin.numbers': '数値とカウント',
+  'settings.highlight.builtin.url': 'ウェブリンク',
   'settings.theme.accent': 'タブのアクセントカラー',
   'settings.theme.accentDesc': 'アクティブなタブの枠線、サイドバーのインジケーター、SSH バッジのアクセントカラー',
   'settings.theme.customBadge': 'カスタム',
diff --git a/src/shared/i18n/dicts/ja/ssh.ts b/src/shared/i18n/dicts/ja/ssh.ts
index b85f49a..5550004 100644
--- a/src/shared/i18n/dicts/ja/ssh.ts
+++ b/src/shared/i18n/dicts/ja/ssh.ts
@@ -13,7 +13,7 @@ const ssh: Record<string, string> = {
   'ssh.fields.askPasswordHint':
     'オンにすると毎回の接続でパスワード入力ダイアログを表示し、保存済みのパスワードを使いません',
   'ssh.fields.passwordPlaceholder': '編集時に空欄のままにすると保存済みのパスワードを保持します',
-  'ssh.fields.keyPath': '秘密鍵のパス（サーバー上の秘密鍵のパス、省略可）',
+  'ssh.fields.keyPath': '秘密鍵ファイルのパス（このコンピューター上のパス、省略可）',
   'ssh.fields.keyContent': '秘密鍵の内容',
   'ssh.fields.keyContentPlaceholder':
     '秘密鍵の内容を貼り付けます。空欄の場合は上のパスを使用します（編集時に空欄のままにすると保存済みの秘密鍵を保持します）',
@@ -102,6 +102,8 @@ const ssh: Record<string, string> = {
   'ssh.file.up': '親フォルダへ',
   'ssh.file.refresh': '更新',
   'ssh.file.uploadFile': 'ファイルをアップロード',
+  'ssh.file.overwriteTitle': '既存のファイルを上書きしますか？',
+  'ssh.file.overwriteDesc': '対象ディレクトリに同名のファイルが存在します。アップロードすると内容が上書きされます。',
   'ssh.file.downloadSelected': '選択項目をダウンロード',
   'ssh.file.permOwner': '権限 / 所有者',
   'ssh.file.open': '開く',
diff --git a/src/shared/i18n/dicts/zh-CN/main.ts b/src/shared/i18n/dicts/zh-CN/main.ts
index f4da4aa..7881784 100644
--- a/src/shared/i18n/dicts/zh-CN/main.ts
+++ b/src/shared/i18n/dicts/zh-CN/main.ts
@@ -27,6 +27,7 @@ const main: Record<string, string> = {
   'main.sftp.deleteFailed': '删除失败: {detail}',
   'main.sftp.invalidMode': '非法权限值: {mode}',
   'main.sftp.invalidUidGid': '非法 uid/gid',
+  'main.sftp.commandTimeout': '命令执行超时',
   'main.sftp.commandExitCode': '命令退出码 {code}',
   'main.sftp.cancelled': '已取消',
 
@@ -47,6 +48,7 @@ const main: Record<string, string> = {
 
   'main.sysinfo.sessionGone': 'SSH 会话不存在或已断开',
   'main.sysinfo.execFailed': 'SSH exec 失败',
+  'main.sysinfo.pollTimeout': '监控命令响应超时',
   'main.sysinfo.parseFailed': '解析失败: {message}',
   'main.pty.serviceNotReady': 'SSH 会话服务尚未初始化',
   'main.pty.missingConnectionId': 'SSH 会话缺少 connectionId',
diff --git a/src/shared/i18n/dicts/zh-CN/settings.ts b/src/shared/i18n/dicts/zh-CN/settings.ts
index 1aa790c..69cb63e 100644
--- a/src/shared/i18n/dicts/zh-CN/settings.ts
+++ b/src/shared/i18n/dicts/zh-CN/settings.ts
@@ -92,6 +92,11 @@ const settings: Record<string, string> = {
     '配合全局键可在任何界面唤起/隐藏窗口；若注册失败（与其他软件冲突）则不生效，应用不会报错。',
   'settings.system.shortcutRecording': '按下组合键…',
   'settings.system.shortcutPlaceholder': '点击后按下快捷键，留空禁用',
+  'settings.system.shortcutConflict':
+    '该组合键已被应用内快捷键占用（Ctrl+= / Ctrl+- / Ctrl+0 / Ctrl+PgUp / Ctrl+PgDn），请换一个。',
+  'settings.resetTerminal': '恢复默认终端设置',
+  'settings.resetTerminalTitle': '恢复默认终端设置？',
+  'settings.resetTerminalDesc': '字体、光标、渲染与主题等全部终端设置将恢复为默认值。',
   'settings.highlight.alert':
     '自定义高亮可增强显示效果，但会略微增加性能消耗。规则按优先级顺序应用。PS: 高亮在写入终端时注入颜色，对已有回滚内容不生效',
   'settings.highlight.enabled': '启用',
@@ -115,6 +120,17 @@ const settings: Record<string, string> = {
   'settings.highlight.resetOk': '恢复',
   'settings.highlight.createTitle': '新建高亮规则',
   'settings.highlight.editTitle': '编辑高亮规则',
+  'settings.highlight.builtin.perm': 'Linux 权限与用户',
+  'settings.highlight.builtin.path': 'Linux 文件路径',
+  'settings.highlight.builtin.shellkw': 'Shell 关键字与流程',
+  'settings.highlight.builtin.okstate': '成功状态',
+  'settings.highlight.builtin.badstate': '错误/警告状态',
+  'settings.highlight.builtin.quoted': '字符串与引号',
+  'settings.highlight.builtin.envvar': '环境变量与参数',
+  'settings.highlight.builtin.ipv4': '网络与 IP 地址',
+  'settings.highlight.builtin.datetime': '时间与日期',
+  'settings.highlight.builtin.numbers': '数字与计数',
+  'settings.highlight.builtin.url': '网址链接',
   'settings.theme.accent': '标签强调色',
   'settings.theme.accentDesc': '活动标签边框、侧栏指示条与 SSH 徽章的强调颜色',
   'settings.theme.customBadge': '自定义',
diff --git a/src/shared/i18n/dicts/zh-CN/ssh.ts b/src/shared/i18n/dicts/zh-CN/ssh.ts
index 9620f35..89c7d65 100644
--- a/src/shared/i18n/dicts/zh-CN/ssh.ts
+++ b/src/shared/i18n/dicts/zh-CN/ssh.ts
@@ -11,7 +11,7 @@ const ssh: Record<string, string> = {
   'ssh.fields.askPasswordLabel': '连接时询问密码',
   'ssh.fields.askPasswordHint': '开启后每次连接弹出对话框输入密码，不再使用已保存的密码',
   'ssh.fields.passwordPlaceholder': '编辑时留空表示保留已保存的密码',
-  'ssh.fields.keyPath': '私钥路径（服务器上的本地私钥路径，可留空）',
+  'ssh.fields.keyPath': '私钥文件路径（本机路径，可留空）',
   'ssh.fields.keyContent': '私钥内容',
   'ssh.fields.keyContentPlaceholder':
     '粘贴私钥内容；留空则使用上面的路径（编辑时留空表示保留已保存的私钥）',
@@ -94,6 +94,8 @@ const ssh: Record<string, string> = {
   'ssh.file.up': '上一级',
   'ssh.file.refresh': '刷新',
   'ssh.file.uploadFile': '上传文件',
+  'ssh.file.overwriteTitle': '覆盖已存在的文件？',
+  'ssh.file.overwriteDesc': '目标目录已存在同名文件，上传将覆盖其内容。',
   'ssh.file.downloadSelected': '下载选中项',
   'ssh.file.permOwner': '权限 / 属主',
   'ssh.file.open': '打开',
diff --git a/src/shared/i18n/dicts/zh-TW/main.ts b/src/shared/i18n/dicts/zh-TW/main.ts
index 5589b54..d258eb6 100644
--- a/src/shared/i18n/dicts/zh-TW/main.ts
+++ b/src/shared/i18n/dicts/zh-TW/main.ts
@@ -27,6 +27,7 @@ const main: Record<string, string> = {
   'main.sftp.deleteFailed': '刪除失敗: {detail}',
   'main.sftp.invalidMode': '權限值無效: {mode}',
   'main.sftp.invalidUidGid': 'uid/gid 無效',
+  'main.sftp.commandTimeout': '命令執行逾時',
   'main.sftp.commandExitCode': '指令結束碼 {code}',
   'main.sftp.cancelled': '已取消',
 
@@ -47,6 +48,7 @@ const main: Record<string, string> = {
 
   'main.sysinfo.sessionGone': 'SSH 工作階段不存在或已中斷',
   'main.sysinfo.execFailed': 'SSH exec 失敗',
+  'main.sysinfo.pollTimeout': '監控命令回應逾時',
   'main.sysinfo.parseFailed': '解析失敗: {message}',
   'main.pty.serviceNotReady': 'SSH 工作階段服務尚未初始化',
   'main.pty.missingConnectionId': 'SSH 工作階段缺少 connectionId',
diff --git a/src/shared/i18n/dicts/zh-TW/settings.ts b/src/shared/i18n/dicts/zh-TW/settings.ts
index d1334bb..b9e33e4 100644
--- a/src/shared/i18n/dicts/zh-TW/settings.ts
+++ b/src/shared/i18n/dicts/zh-TW/settings.ts
@@ -92,6 +92,11 @@ const settings: Record<string, string> = {
     '搭配全域鍵可在任何畫面喚出／隱藏視窗；若註冊失敗（與其他軟體衝突）則不會生效，應用程式也不會報錯。',
   'settings.system.shortcutRecording': '請按下組合鍵…',
   'settings.system.shortcutPlaceholder': '點擊後按下快速鍵，留空為停用',
+  'settings.system.shortcutConflict':
+    '此組合鍵已被應用內快捷鍵佔用（Ctrl+= / Ctrl+- / Ctrl+0 / Ctrl+PgUp / Ctrl+PgDn），請換一個。',
+  'settings.resetTerminal': '恢復預設終端設定',
+  'settings.resetTerminalTitle': '恢復預設終端設定？',
+  'settings.resetTerminalDesc': '字體、游標、渲染與主題等全部終端設定將恢復為預設值。',
   'settings.highlight.alert':
     '自訂高亮可強化顯示效果，但會略微增加效能負擔。規則依優先順序套用。PS：高亮是在寫入終端時注入顏色，對既有的回捲內容不生效',
   'settings.highlight.enabled': '啟用',
@@ -115,6 +120,17 @@ const settings: Record<string, string> = {
   'settings.highlight.resetOk': '還原',
   'settings.highlight.createTitle': '新增高亮規則',
   'settings.highlight.editTitle': '編輯高亮規則',
+  'settings.highlight.builtin.perm': 'Linux 權限與使用者',
+  'settings.highlight.builtin.path': 'Linux 檔案路徑',
+  'settings.highlight.builtin.shellkw': 'Shell 關鍵字與流程',
+  'settings.highlight.builtin.okstate': '成功狀態',
+  'settings.highlight.builtin.badstate': '錯誤/警告狀態',
+  'settings.highlight.builtin.quoted': '字串與引號',
+  'settings.highlight.builtin.envvar': '環境變數與參數',
+  'settings.highlight.builtin.ipv4': '網路與 IP 位址',
+  'settings.highlight.builtin.datetime': '時間與日期',
+  'settings.highlight.builtin.numbers': '數字與計數',
+  'settings.highlight.builtin.url': '網址連結',
   'settings.theme.accent': '標籤強調色',
   'settings.theme.accentDesc': '作用中標籤的邊框、側邊欄指示條與 SSH 徽章的強調顏色',
   'settings.theme.customBadge': '自訂',
diff --git a/src/shared/i18n/dicts/zh-TW/ssh.ts b/src/shared/i18n/dicts/zh-TW/ssh.ts
index f040d23..f640383 100644
--- a/src/shared/i18n/dicts/zh-TW/ssh.ts
+++ b/src/shared/i18n/dicts/zh-TW/ssh.ts
@@ -11,7 +11,7 @@ const ssh: Record<string, string> = {
   'ssh.fields.askPasswordLabel': '連線時詢問密碼',
   'ssh.fields.askPasswordHint': '開啟後每次連線彈出對話框輸入密碼，不再使用已儲存的密碼',
   'ssh.fields.passwordPlaceholder': '編輯時留空表示保留已儲存的密碼',
-  'ssh.fields.keyPath': '私鑰路徑（伺服器上的本機私鑰路徑，可留空）',
+  'ssh.fields.keyPath': '私鑰檔案路徑（本機路徑，可留空）',
   'ssh.fields.keyContent': '私鑰內容',
   'ssh.fields.keyContentPlaceholder':
     '貼上私鑰內容；留空則使用上面的路徑（編輯時留空表示保留已儲存的私鑰）',
@@ -94,6 +94,8 @@ const ssh: Record<string, string> = {
   'ssh.file.up': '上一層',
   'ssh.file.refresh': '重新整理',
   'ssh.file.uploadFile': '上傳檔案',
+  'ssh.file.overwriteTitle': '覆蓋已存在的檔案？',
+  'ssh.file.overwriteDesc': '目標目錄已存在同名檔案，上傳將覆蓋其內容。',
   'ssh.file.downloadSelected': '下載選取項目',
   'ssh.file.permOwner': '權限 / 擁有者',
   'ssh.file.open': '開啟',
diff --git a/src/shared/i18n/index.ts b/src/shared/i18n/index.ts
index 30bbb5f..cd0dc9f 100644
--- a/src/shared/i18n/index.ts
+++ b/src/shared/i18n/index.ts
@@ -53,6 +53,12 @@ const DICTS: Record<Language, Dict> = {
   ja
 }
 
+/** Own-property read: dictionary literals would otherwise answer `constructor`,
+ *  `toString`, … straight out of Object.prototype and then throw in replace(). */
+function lookup(dict: Dict, key: string): string | undefined {
+  return Object.prototype.hasOwnProperty.call(dict, key) ? dict[key] : undefined
+}
+
 let current: Language = DEFAULT_LANGUAGE
 const listeners = new Set<(lang: Language) => void>()
 
@@ -75,7 +81,7 @@ export function onLanguageChange(cb: (lang: Language) => void): () => void {
 
 /** Translate `key`; `{name}` placeholders are filled from `vars`. */
 export function t(key: string, vars?: Record<string, string | number>): string {
-  const raw = DICTS[current][key] ?? DICTS[DEFAULT_LANGUAGE][key] ?? key
+  const raw = lookup(DICTS[current], key) ?? lookup(DICTS[DEFAULT_LANGUAGE], key) ?? key
   if (!vars) return raw
   return raw.replace(/\{(\w+)\}/g, (match, name: string) =>
     vars[name] === undefined ? match : String(vars[name])
diff --git a/src/shared/ipc.ts b/src/shared/ipc.ts
index 3f79b5c..bdc376d 100644
--- a/src/shared/ipc.ts
+++ b/src/shared/ipc.ts
@@ -97,6 +97,8 @@ export const Ipc = {
   UPDATE_DOWNLOAD: 'update:download',
   UPDATE_INSTALL: 'update:install',
   UPDATE_CHANGELOG: 'update:changelog',
+  /** renderer pulls the current updater state without triggering a check */
+  UPDATE_STATE_GET: 'update:stateGet',
   /** main -> renderer broadcast: UpdateState */
   UPDATE_STATE: 'update:state',