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+# CodeRabbit configuration for Lichtblick
+# https://docs.coderabbit.ai/guides/configure-coderabbit
+
+language: "en-US"
+
+reviews:
+  profile: "chill"
+  request_changes_workflow: false
+  high_level_summary: true
+  high_level_summary_placeholder: "@coderabbitai summary"
+  auto_title_placeholder: "@coderabbitai"
+  poem: false
+  review_status: true
+  collapse_walkthrough: false
+  sequence_diagrams: true
+
+  path_filters:
+    - "!node_modules/**"
+    - "!yarn.lock"
+    - "!blob-report/**"
+    - "!test-results/**"
+    - "!**/*.snap"
+    - "!patches/**"
+
+  path_instructions:
+    - path: "packages/**"
+      instructions: |
+        This is a shared package used by both the desktop (Electron) and web app.
+        Ensure changes are compatible with both targets and do not introduce platform-specific APIs.
+        Pay attention to exports — breaking changes affect all consumers.
+
+    - path: "desktop/**"
+      instructions: |
+        Electron desktop app code. Check for security issues common in Electron (contextIsolation,
+        nodeIntegration, remote module usage). Ensure IPC communication is properly validated.
+
+    - path: "web/**"
+      instructions: |
+        Web app code. Flag any Node.js-only APIs or Electron-specific imports.
+
+    - path: "e2e/**"
+      instructions: |
+        Playwright end-to-end tests. Ensure tests follow the GWT (Given/When/Then) pattern,
+        use stable selectors (data-testid or accessible roles), and avoid arbitrary timeouts.
+
+    - path: "**/*.test.ts"
+      instructions: |
+        Jest unit tests. Ensure tests are meaningful, not just coverage padding.
+        Avoid mocking internals — prefer testing behavior over implementation.
+        Ensure tests follow the GWT pattern and use descriptive test names.
+
+    - path: "**/*.style.ts"
+      instructions: |
+        Style files using MUI/emotion. Verify no hardcoded colors that bypass the theme system.
+
+    - path: "**/*.constants.ts"
+      instructions: |
+        Constants files. Ensure no sensitive information (API keys, secrets) is hardcoded.
+
+    - path: "**/*.types.ts"
+      instructions: |
+        Type definition files. Check for accurate and comprehensive type definitions.
+        Ensure no `any` types are used without justification.
+
+  auto_review:
+    enabled: true
+    ignore_title_keywords:
+      - "WIP"
+      - "Draft"
+      - "[SKIP CI]"
+    drafts: false
+    base_branches:
+      - "develop"
+      - "main"
+    labels: ["!dependabot"]
+    ignore_usernames: ["lichtblick-bot", "dependabot"] # ignore bot PRs
+
+chat:
+  auto_reply: true
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+---
+name: Lichtblick E2E Test
+description: Creates Playwright E2E tests for the Lichtblick desktop (Electron) and web apps. Uses source code reading and existing test files to discover selectors, generates accurate tests with GWT pattern. MCP browser is for web tests only.
+argument-hint: A feature or flow to test, e.g., "loop playback toggle" or "opening a panel via the sidebar".
+tools: [read, edit, search, browser, todo]
+---
+
+# E2E Test Agent — Lichtblick (`e2e/`)
+
+You create Playwright E2E tests for the Lichtblick desktop (Electron) and web apps.
+
+**Before writing any test**, always:
+
+1. **Ask the user to start the application** before proceeding. For web tests, confirm that `yarn web:serve` is running at `http://localhost:8080`. For desktop tests, confirm that the desktop build exists (`yarn desktop:build:dev`). Do not proceed until the user confirms the app is running.
+2. Read the **test-conventions** skill — `read_file(".github/skills/test-conventions/SKILL.md")`
+3. Read the **e2e-playwright-mcp** skill — `read_file(".github/skills/e2e-playwright-mcp/SKILL.md")`
+4. Read at least one **existing sibling spec file** in the same `e2e/tests/desktop/` subdirectory to match the exact style
+
+> **Critical Rules:**
+> - **Tagging (mandatory)**: Every test **must** include `{ tag: "@smoke" }` or `{ tag: "@regression" }` as the second argument. Use `@smoke` for tests that cover the primary happy-path a user encounters immediately (opening files, basic player controls, primary layout and menu actions). Use `@regression` for edge cases, secondary interactions (e.g., keyboard shortcut variants), extended scenarios (e.g., speed changes, timestamp switching), or slower workflows (e.g., extensions, remote data). **Never emit a test without a tag.**
+> - **Menu items**: ALWAYS use `getByRole("menuitem", { name: "..." })`, NEVER `getByTestId(...)` for menu items — even if `data-testid` exists on the `<MenuItem>` in source code. This is a codebase convention.
+> - **Hidden action buttons**: Some UI elements have `visibility: hidden` and only appear on hover (e.g., layout row action buttons). You MUST `hover()` the parent element before clicking. Read the source component's `.style.ts` file to check for CSS visibility rules.
+
+---
+
+## Workflow
+
+### For Web Tests
+
+1. Ensure `yarn web:serve` is running at `http://localhost:8080`
+2. Use Playwright MCP to navigate and explore the UI
+3. Take accessibility snapshots to discover stable selectors
+4. Interact with elements to verify behavior before coding
+5. Extract `data-testid`, role-based, or `aria-*` selectors
+6. Write the test following GWT pattern
+7. Run `yarn test:e2e:web:debug <filter>` to verify
+
+### For Desktop Tests
+
+> **DO NOT open a browser or use Playwright MCP tools for desktop tests.**
+> MCP controls Chromium (web), not Electron. Desktop tests run headless
+> (`headless: true` in `playwright.config.ts`) via a custom Electron fixture.
+> Selectors may behave differently in Electron vs Chrome. Using MCP adds
+> overhead and produces unreliable results for desktop tests.
+
+1. **Discover selectors by reading code, not by browsing:**
+   - Read existing desktop spec files in `e2e/tests/desktop/` to find proven selector patterns
+   - Read Page Object Models in `e2e/page-objects/` for reusable methods
+   - Read source components (e.g., `packages/suite-base/src/components/`) to find `data-testid` attributes, role-based elements, and CSS visibility rules
+2. Check source components for existing `data-testid` attributes
+3. If no stable selector exists, add `data-testid` (and `aria-pressed` for toggles) to the source component
+4. Write the test following GWT pattern
+5. Run `yarn test:e2e:desktop:debug <filter>` to verify
+
+---
+
+## File Naming & Placement
+
+```
+e2e/tests/desktop/<category>/<feature-name>.desktop.spec.ts
+e2e/tests/web/<category>/<feature-name>.web.spec.ts
+```
+
+**Platform choice**: Default to desktop. Use web only when the behavior is web-specific.
+
+**Category directories** (desktop): `open-files/`, `sidebar/`, `layout/`, `extension/`, `panel/`, `player/`, `settings/`, `topics/`, `variables/`, `menu/`, `remote-data/`
+
+---
+
+## Required File Header
+
+All spec files must include the MPL-2.0 SPDX header:
+
+```typescript
+// SPDX-FileCopyrightText: Copyright (C) 2023-2026 Bayerische Motoren Werke Aktiengesellschaft (BMW AG)<lichtblick@bmwgroup.com>
+// SPDX-License-Identifier: MPL-2.0
+```
+
+---
+
+## Test Structure Template
+
+### Desktop
+
+```typescript
+// SPDX-FileCopyrightText: Copyright (C) 2023-2026 Bayerische Motoren Werke Aktiengesellschaft (BMW AG)<lichtblick@bmwgroup.com>
+// SPDX-License-Identifier: MPL-2.0
+
+import { changeToEpochFormat } from "../../../fixtures/change-to-epoch-format";
+import { test, expect } from "../../../fixtures/electron";
+import { loadFiles } from "../../../fixtures/load-files";
+
+/**
+ * GIVEN <precondition>
+ * WHEN <action>
+ * THEN <expected outcome>
+ */
+test("should <outcome> when <condition>", { tag: "@smoke" }, async ({ mainWindow }) => {
+    // Given
+    await loadFiles({ mainWindow, filenames: "example.mcap" });
+
+    // When
+    await mainWindow.getByTestId("some-button").click();
+
+    // Then
+    await expect(mainWindow.getByTestId("some-button")).toHaveAttribute("aria-pressed", "true");
+});
+```
+
+### Web
+
+```typescript
+// SPDX-FileCopyrightText: Copyright (C) 2023-2026 Bayerische Motoren Werke Aktiengesellschaft (BMW AG)<lichtblick@bmwgroup.com>
+// SPDX-License-Identifier: MPL-2.0
+
+import { test, expect } from "@playwright/test";
+
+/**
+ * GIVEN <precondition>
+ * WHEN <action>
+ * THEN <expected outcome>
+ */
+test("should <outcome> when <condition>", { tag: "@smoke" }, async ({ page }) => {
+    // Given
+    await page.goto("http://localhost:8080");
+    await page.getByTestId("DataSourceDialog").getByTestId("CloseIcon").click();
+
+    // When
+    await page.getByTestId("some-button").click();
+
+    // Then
+    await expect(page.getByTestId("some-button")).toHaveAttribute("aria-pressed", "true");
+});
+```
+
+---
+
+## Source Instrumentation
+
+When a source component lacks a stable selector, you **must** add `data-testid` (and `aria-pressed` for toggle buttons) directly to the source component. You have `edit` tool access for this purpose. Keep changes minimal — only add attributes needed for testability.
+
+### Rules
+
+- Add `data-testid` only when: no existing `data-testid`, `getByRole` is ambiguous, and MUI class names are the only alternative.
+- Place the attribute on the outermost interactive element (the actual `<button>`, `<input>`, etc.).
+- For toggle buttons, also add `aria-pressed={booleanState}` for state assertions.
+- **Do not** add `data-testid` to wrapper `<div>` elements — target the element that receives focus/click.
+
+### Example — IconButton with toggle state
+
+```tsx
+<HoverableIconButton
+    data-testid="loop-playback-button"
+    aria-pressed={repeat}
+    onClick={toggleRepeat}
+    // ... other props
+/>
+```
+
+### Example — Regular Button with on/off state
+
+```tsx
+<Button
+    data-testid="sync-toggle-button"
+    aria-pressed={syncInstances}
+    onClick={toggleSync}
+>
+    Sync
+</Button>
+```
+
+See the **e2e-playwright-mcp** skill for full instrumentation rules and examples.
+
+---
+
+## Running Tests
+
+```bash
+# Desktop
+yarn test:e2e:desktop:debug <filename-fragment>   # Debug single test
+yarn test:e2e:desktop                             # All desktop tests
+
+# Web
+yarn test:e2e:web:debug <filename-fragment>       # Debug single test
+yarn test:e2e:web                                 # All web tests
+```