fix(updater): failed update check never blocks startup

docs/DEVELOPMENT.md

@@ -179,15 +179,19 @@ The `latest.json` manifest supports optional policy fields:
 On launch, Basebuild shows a startup splash that checks for updates before
 the main shell becomes interactive. The splash has these states:
 
-- **Checking** — Shows current version and update-check progress.
+- **Checking** — Shows current version and update-check progress. Runs on
+  Windows, macOS, and Linux. After 8 seconds the app opens anyway and the
+  check finishes in the background.
 - **Optional update** — Shows target version, summary, and `Upgrade` /
   `Skip update for now` buttons. The skip is version-scoped: the user is
   not prompted again for the same target version, but will be prompted for
   a newer release.
 - **Mandatory update** — Hides the skip button and auto-starts the update
   when the running version is below `minimumSupportedVersion`.
 - **Progress** — Shows download/install progress bar and step text.
-- **Error** — Shows actionable diagnostics with retry and "Continue anyway".
+- **Check failed** — never blocks startup: the app opens and the taskbar
+  update control shows the failure with a retry. The backend also logs it to
+  stderr with an `[updater]` prefix.
 
 The existing in-app update UI (taskbar button + Settings → Updates tab)
 remains functional after startup for manual checks and installs.

docs/agents/desktop-shell.md

@@ -297,7 +297,8 @@ Before the main shell renders, Basebuild shows a startup update splash
 that checks for updates. The splash displays the current build version
 and transitions through these states:
 
-- **Checking** — update check in progress.
+- **Checking** — update check in progress (every platform). After 8 seconds
+  the shell opens and the check continues in the background.
 - **Optional update** — target version, summary, and `Upgrade` / `Skip
   update for now` buttons. Skip is version-scoped: the same target version
   is not prompted again, but a newer release will prompt.
@@ -306,7 +307,8 @@ and transitions through these states:
   update auto-starts.
 - **Progress** — download progress bar and step text (downloading,
   installing, restarting).
-- **Error** — actionable diagnostics with retry and "Continue anyway".
+- **Check failed** — the shell opens immediately; the taskbar update control
+  surfaces the failure and its retry.
 
 The splash does not replace the in-app update controls. The taskbar
 update button and Settings → Updates tab remain functional after startup.

src-tauri/src/commands/updater.rs

@@ -288,14 +288,19 @@ pub async fn check_for_updates(app: AppHandle) -> Result<UpdateInfo, String> {
             skipped: false,
         });
     }
-    let updater = app
-        .updater()
-        .map_err(|e| format!("Failed to get updater: {e}"))?;
+    let updater = app.updater().map_err(|e| {
+        let message = format!("Failed to get updater: {e}");
+        eprintln!("[updater] {message}");
+        message
+    })?;
 
     let update = updater.check().await.map_err(|e| {
         let status = UpdateChannelStatus::from_plugin_error(&e);
         let explanation = status.explanation();
-        format!("Failed to check for updates: {e} | channel_status={status:?} | {explanation}")
+        let message =
+            format!("Failed to check for updates: {e} | channel_status={status:?} | {explanation}");
+        eprintln!("[updater] {message}");
+        message
     })?;
 
     match update {

src/components/layout/StartupSplash.tsx

@@ -2,7 +2,6 @@ import { useEffect, useState } from "react";
 import { AlertTriangle, Download, RefreshCw, X } from "lucide-react";
 import type { UpdaterState } from "../../state/updater";
 import { appVersion } from "../../lib/app";
-import { CopyButton } from "./CopyButton";
 import { t } from "../../i18n";
 
 type StartupSplashProps = {
@@ -15,7 +14,6 @@ type SplashPhase =
   | "checking"
   | "mandatory"
   | "progress"
-  | "error"
   | "ready";
 
 const SPLASH_CHECK_TIMEOUT_MS = 8_000;
@@ -65,9 +63,11 @@ export function StartupSplash({ updates, onComplete }: StartupSplashProps) {
       return;
     }
 
-    // Error state.
+    // A failed check never blocks startup: enter the app; the taskbar update
+    // control shows the failure and offers a retry.
     if (status === "error") {
-      setPhase("error");
+      setPhase("ready");
+      onComplete();
       return;
     }
 
@@ -104,11 +104,6 @@ export function StartupSplash({ updates, onComplete }: StartupSplashProps) {
     onComplete();
   };
 
-  const handleRetry = () => {
-    void updates.checkNow();
-    setAutoStarted(false);
-  };
-
   // Progress percentage from backend events.
   const progressPct = (() => {
     const p = updates.progress;
@@ -191,49 +186,6 @@ export function StartupSplash({ updates, onComplete }: StartupSplashProps) {
           </div>
         )}
 
-        {phase === "error" && (
-          <div className="splash-update-info">
-            <div className="splash-update-title">
-              <AlertTriangle size={14} /> {t("startupSplash.updateCheckFailed")}
-            </div>
-            <p className="splash-update-summary text-muted text-sm">
-              {updates.info?.channelExplanation ?? updates.error ?? t("startupSplash.couldNotCheckForUpdates")}
-            </p>
-            {updates.info?.rawError ? (
-              <details className="update-raw-error">
-                <summary className="text-muted text-sm">{t("startupSplash.rawError")}</summary>
-                <pre className="text-sm mono">{updates.info.rawError}</pre>
-              </details>
-            ) : null}
-            {updates.info?.rawError ? (
-              <div className="splash-error-copy">
-                <CopyButton text={updates.info.rawError} label={t("startupSplash.copyError")} />
-              </div>
-            ) : null}
-            <div className="splash-actions">
-              <button
-                className="btn btn-sm"
-                type="button"
-                title={t("startupSplash.retryUpdateCheck")}
-                onClick={handleRetry}
-              >
-                <RefreshCw size={12} /> {t("startupSplash.retry")}
-              </button>
-              <button
-                className="btn btn-ghost btn-sm"
-                type="button"
-                title={t("startupSplash.continueToBasebuildWithoutUpdating")}
-                onClick={() => {
-                  setPhase("ready");
-                  onComplete();
-                }}
-              >
-                {t("startupSplash.continueAnyway")}
-              </button>
-            </div>
-          </div>
-        )}
-
         {phase === "checking" && (
           <button
             className="btn btn-ghost btn-sm splash-skip-check"

src/i18n/en/layout.ts

@@ -708,14 +708,6 @@ export const layoutEn = {
   "startupSplash.minimumSupportedVersionNote": " Minimum supported version is {minimumSupportedVersion}.",
   "startupSplash.updatingToBasebuild": "Updating to Basebuild {version}",
   "startupSplash.updating": "Updating…",
-  "startupSplash.updateCheckFailed": "Update check failed",
-  "startupSplash.couldNotCheckForUpdates": "Could not check for updates.",
-  "startupSplash.rawError": "Raw error",
-  "startupSplash.copyError": "Copy error",
-  "startupSplash.retry": "Retry",
-  "startupSplash.retryUpdateCheck": "Retry update check",
-  "startupSplash.continueAnyway": "Continue anyway",
-  "startupSplash.continueToBasebuildWithoutUpdating": "Continue to Basebuild without updating",
   "startupSplash.skip": "Skip",
   "startupSplash.skipUpdateCheckAndContinue": "Skip update check and continue to Basebuild",
   "statusBar.clickToViewAllWarnings": "Click to view all warnings and errors",

src/i18n/zh-CN/layout.ts

@@ -708,14 +708,6 @@ export const layoutZhCN = {
   "startupSplash.minimumSupportedVersionNote": " 最低支持版本为 {minimumSupportedVersion}。",
   "startupSplash.updatingToBasebuild": "正在更新至 Basebuild {version}",
   "startupSplash.updating": "正在更新…",
-  "startupSplash.updateCheckFailed": "更新检查失败",
-  "startupSplash.couldNotCheckForUpdates": "无法检查更新。",
-  "startupSplash.rawError": "原始错误",
-  "startupSplash.copyError": "复制错误",
-  "startupSplash.retry": "重试",
-  "startupSplash.retryUpdateCheck": "重试更新检查",
-  "startupSplash.continueAnyway": "仍然继续",
-  "startupSplash.continueToBasebuildWithoutUpdating": "不更新，继续使用 Basebuild",
   "startupSplash.skip": "跳过",
   "startupSplash.skipUpdateCheckAndContinue": "跳过更新检查，继续进入 Basebuild",
   "statusBar.clickToViewAllWarnings": "点击查看所有警告和错误",

src/i18n/zh-TW/layout.ts

@@ -710,14 +710,6 @@ export const layoutZhTW = {
   "startupSplash.minimumSupportedVersionNote": " 最低支援版本為 {minimumSupportedVersion}。",
   "startupSplash.updatingToBasebuild": "正在更新至 Basebuild {version}",
   "startupSplash.updating": "正在更新…",
-  "startupSplash.updateCheckFailed": "更新檢查失敗",
-  "startupSplash.couldNotCheckForUpdates": "無法檢查更新。",
-  "startupSplash.rawError": "原始錯誤",
-  "startupSplash.copyError": "複製錯誤",
-  "startupSplash.retry": "重試",
-  "startupSplash.retryUpdateCheck": "重試更新檢查",
-  "startupSplash.continueAnyway": "仍然繼續",
-  "startupSplash.continueToBasebuildWithoutUpdating": "不更新，繼續使用 Basebuild",
   "startupSplash.skip": "跳過",
   "startupSplash.skipUpdateCheckAndContinue": "跳過更新檢查，繼續進入 Basebuild",
   "statusBar.clickToViewAllWarnings": "點選檢視所有警告和錯誤",

src/styles/globals.css

@@ -3903,7 +3903,6 @@ mark.chat-search-highlight-active { background: var(--bb-warning); color: var(--
 @keyframes splash-indeterminate { 0% { transform: translateX(-100%); } 100% { transform: translateX(350%); } }
 .splash-progress-message { text-align: center; line-height: 1.4; }
 .splash-skip-check { margin-top: 8px; }
-.splash-error-copy { display: flex; justify-content: center; }
 .splash-spinner { flex-shrink: 0; }
 .workspace-splash { transition: opacity 0.2s ease-out; }
 .workspace-splash-fading { opacity: 0; }