fix: E2E test stability and UI performance improvements

apps/ui/src/components/views/board-view/hooks/use-board-effects.ts

@@ -119,7 +119,6 @@ export function useBoardEffects({
     if (featuresFingerprint && !isLoading) {
       checkAllContexts();
     }
-    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [featuresFingerprint, isLoading, checkContextExists, setFeaturesWithContext]);
 
   // Re-check context when a feature stops, completes, or errors

apps/ui/src/components/views/board-view/worktree-panel/components/dev-server-logs-panel.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useRef, useCallback, useState } from 'react';
+import { useEffect, useRef, useCallback, useState, useMemo } from 'react';
 import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog';
 import { Button } from '@/components/ui/button';
 import {
@@ -54,6 +54,8 @@ export function DevServerLogsPanel({
 
   const {
     logs,
+    logsVersion,
+    didTrim,
     isRunning,
     isLoading,
     error,
@@ -81,8 +83,9 @@ export function DevServerLogsPanel({
       return;
     }
 
-    // If logs got shorter (e.g., cleared), rewrite all
-    if (logs.length < lastLogsLengthRef.current) {
+    // If logs got shorter (e.g., cleared) or buffer was trimmed (content shifted),
+    // do a full rewrite so the terminal stays in sync
+    if (logs.length < lastLogsLengthRef.current || didTrim) {
       xtermRef.current.write(logs);
       lastLogsLengthRef.current = logs.length;
       return;
@@ -94,7 +97,7 @@ export function DevServerLogsPanel({
       xtermRef.current.append(newContent);
       lastLogsLengthRef.current = logs.length;
     }
-  }, [logs, worktree?.path]);
+  }, [logs, logsVersion, didTrim, worktree?.path]);
 
   // Reset when panel opens with a new worktree
   useEffect(() => {
@@ -123,10 +126,19 @@ export function DevServerLogsPanel({
     }
   }, []);
 
+  const lineCount = useMemo(() => {
+    if (!logs) return 0;
+    // Count newlines directly instead of allocating a split array
+    let count = 1;
+    for (let i = 0; i < logs.length; i++) {
+      if (logs.charCodeAt(i) === 10) count++;
+    }
+    return count;
+  }, [logs]);
+
   if (!worktree) return null;
 
   const formattedStartTime = formatStartedAt(startedAt);
-  const lineCount = logs ? logs.split('\n').length : 0;
 
   return (
     <Dialog open={open} onOpenChange={(isOpen) => !isOpen && onClose()}>

apps/ui/src/components/views/board-view/worktree-panel/hooks/use-dev-server-logs.ts

@@ -5,9 +5,16 @@ import { pathsEqual } from '@/lib/utils';
 
 const logger = createLogger('DevServerLogs');
 
+// Maximum log buffer size (characters) - matches server-side MAX_SCROLLBACK_SIZE
+const MAX_LOG_BUFFER_SIZE = 50_000; // ~50KB
+
 export interface DevServerLogState {
   /** The log content (buffered + live) */
   logs: string;
+  /** Incremented whenever logs content changes (including trim+shift) */
+  logsVersion: number;
+  /** True when the latest append caused head truncation */
+  didTrim: boolean;
   /** Whether the server is currently running */
   isRunning: boolean;
   /** Whether initial logs are being fetched */
@@ -52,6 +59,8 @@ interface UseDevServerLogsOptions {
 export function useDevServerLogs({ worktreePath, autoSubscribe = true }: UseDevServerLogsOptions) {
   const [state, setState] = useState<DevServerLogState>({
     logs: '',
+    logsVersion: 0,
+    didTrim: false,
     isRunning: false,
     isLoading: false,
     error: null,
@@ -123,6 +132,8 @@ export function useDevServerLogs({ worktreePath, autoSubscribe = true }: UseDevS
   const clearLogs = useCallback(() => {
     setState({
       logs: '',
+      logsVersion: 0,
+      didTrim: false,
       isRunning: false,
       isLoading: false,
       error: null,
@@ -136,13 +147,27 @@ export function useDevServerLogs({ worktreePath, autoSubscribe = true }: UseDevS
   }, []);
 
   /**
-   * Append content to logs
+   * Append content to logs, enforcing a maximum buffer size to prevent
+   * unbounded memory growth and progressive UI lag.
    */
   const appendLogs = useCallback((content: string) => {
-    setState((prev) => ({
-      ...prev,
-      logs: prev.logs + content,
-    }));
+    setState((prev) => {
+      const combined = prev.logs + content;
+      const didTrim = combined.length > MAX_LOG_BUFFER_SIZE;
+      let newLogs = combined;
+      if (didTrim) {
+        const slicePoint = combined.length - MAX_LOG_BUFFER_SIZE;
+        // Find the next newline after the slice point to avoid cutting a line in half
+        const firstNewlineIndex = combined.indexOf('\n', slicePoint);
+        newLogs = combined.slice(firstNewlineIndex > -1 ? firstNewlineIndex + 1 : slicePoint);
+      }
+      return {
+        ...prev,
+        logs: newLogs,
+        didTrim,
+        logsVersion: prev.logsVersion + 1,
+      };
+    });
   }, []);
 
   // Fetch initial logs when worktreePath changes

apps/ui/tests/features/feature-deep-link.spec.ts

@@ -28,6 +28,7 @@ test.describe('Feature Deep Link', () => {
   let projectPath: string;
   let projectName: string;
 
+  // eslint-disable-next-line no-empty-pattern
   test.beforeEach(async ({}, testInfo) => {
     projectName = `test-project-${testInfo.workerIndex}-${Date.now()}`;
     projectPath = path.join(TEST_TEMP_DIR, projectName);

apps/ui/tests/features/responsive/agent-output-modal-responsive.spec.ts

@@ -13,6 +13,7 @@ import {
   waitForNetworkIdle,
   authenticateForTests,
   handleLoginScreenIfPresent,
+  dismissSandboxWarningIfVisible,
 } from '../../utils';
 
 const TEST_TEMP_DIR = createTempDirPath('responsive-modal-test');
@@ -100,6 +101,9 @@ test.describe('AgentOutputModal Responsive Behavior', () => {
 
     await expect(page.locator('[data-testid="board-view"]')).toBeVisible({ timeout: 10000 });
 
+    // Dismiss sandbox warning dialog if it appears (blocks pointer events)
+    await dismissSandboxWarningIfVisible(page);
+
     // Wait for the verified feature card to appear
     const featureCard = page.locator(`[data-testid="kanban-card-${featureId}"]`);
     await expect(featureCard).toBeVisible({ timeout: 10000 });

apps/ui/tests/features/success-log-contrast.spec.ts

@@ -13,6 +13,7 @@ import {
   waitForNetworkIdle,
   authenticateForTests,
   handleLoginScreenIfPresent,
+  dismissSandboxWarningIfVisible,
 } from '../utils';
 
 /**
@@ -109,6 +110,9 @@ test.describe('Success log output contrast', () => {
 
     await expect(page.locator('[data-testid="board-view"]')).toBeVisible({ timeout: 10000 });
 
+    // Dismiss sandbox warning dialog if it appears (blocks pointer events)
+    await dismissSandboxWarningIfVisible(page);
+
     // Wait for the verified feature card to appear
     const featureCard = page.locator(`[data-testid="kanban-card-${featureId}"]`);
     await expect(featureCard).toBeVisible({ timeout: 10000 });

apps/ui/tests/settings/event-hooks-settings.spec.ts

@@ -12,7 +12,7 @@
  */
 
 import { test, expect, type Page } from '@playwright/test';
-import { authenticateForTests, navigateToSettings } from '../utils';
+import { authenticateForTests, navigateToSettings, waitForSuccessToast } from '../utils';
 
 // Timeout constants for maintainability
 const TIMEOUTS = {
@@ -224,6 +224,9 @@ test.describe('Event Hooks Settings', () => {
     const addButton = dialog.locator('button:has-text("Add Endpoint")').last();
     await addButton.click();
 
+    // Wait for the success toast to confirm the save completed (including API call)
+    await waitForSuccessToast(page, 'Endpoint added', { timeout: 10000 });
+
     // Dialog should close
     await expect(dialog).toBeHidden({ timeout: TIMEOUTS.dialogHidden });
 
@@ -256,16 +259,13 @@ test.describe('Event Hooks Settings', () => {
     // The endpoints tab should show either existing endpoints or the empty state
     // The key is that it should NOT show "empty" if there are endpoints on the server
 
-    // Either we see "No endpoints configured" OR we see endpoint cards
-    const emptyState = page.locator('text=No endpoints configured');
+    // Either we see "No ntfy endpoints configured" OR we see endpoint cards
+    const emptyState = page.locator('text=No ntfy endpoints configured');
     const endpointCard = page.locator('[data-testid="endpoint-card"]').first();
 
-    // One of these should be visible
-    await expect(
-      Promise.race([
-        emptyState.waitFor({ state: 'visible', timeout: 5000 }).then(() => 'empty'),
-        endpointCard.waitFor({ state: 'visible', timeout: 5000 }).then(() => 'card'),
-      ])
-    ).resolves.toBeDefined();
+    // One of these should be visible (use Playwright's .or() to match either locator)
+    await expect(emptyState.or(endpointCard)).toBeVisible({
+      timeout: TIMEOUTS.endpointVisible,
+    });
   });
 });

apps/ui/tests/utils/components/dialogs.ts

@@ -2,6 +2,27 @@ import { Page, Locator } from '@playwright/test';
 import { clickElement } from '../core/interactions';
 import { waitForElement, waitForElementHidden } from '../core/waiting';
 
+/**
+ * Dismiss the sandbox warning dialog if it appears.
+ * This dialog blocks pointer events and must be accepted before interacting
+ * with elements behind it.
+ */
+export async function dismissSandboxWarningIfVisible(page: Page): Promise<void> {
+  const sandboxAcceptBtn = page.locator('button:has-text("I Accept the Risks")');
+  const sandboxVisible = await sandboxAcceptBtn
+    .waitFor({ state: 'visible', timeout: 2000 })
+    .then(() => true)
+    .catch(() => false);
+  if (sandboxVisible) {
+    await sandboxAcceptBtn.click();
+    await page
+      .locator('[role="dialog"][data-state="open"]')
+      .first()
+      .waitFor({ state: 'hidden', timeout: 3000 })
+      .catch(() => {});
+  }
+}
+
 /**
  * Check if the add feature dialog is visible
  */

apps/ui/tests/utils/project/setup.ts

@@ -242,6 +242,7 @@ export async function setupRealProject(
         theme: 'dark',
         sidebarOpen: true,
         maxConcurrency: 3,
+        skipSandboxWarning: true,
       };
       localStorage.setItem('automaker-settings-cache', JSON.stringify(settingsCache));