From 4b7ea239d4765d41c1b1dc9056062315be54a331 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Carlos=20Flor=C3=AAncio?= <carlosmflorencio@gmail.com>
Date: Mon, 24 Aug 2026 19:24:15 +0000
Subject: [PATCH] fix(web): scope task title previews to Kanban (#2939)

---
 apps/web/app/tasks/rich-task-list-row.tsx     |   9 +-
 .../components/kanban-card-content.test.tsx   |  12 +-
 apps/web/components/task/task-item.tsx        |  20 +--
 .../task/task-title-hover-card.test.tsx       |  25 +++-
 .../components/task/task-title-hover-card.tsx |  16 +--
 apps/web/e2e/pages/session-page.ts            |  30 ++--
 .../kanban/task-title-hover-subtasks.spec.ts  |  14 +-
 apps/web/e2e/tests/pr/pr-status-badge.spec.ts |   5 +-
 .../tests/task/create-task-github-url.spec.ts |   4 +-
 .../task/task-title-hover-surfaces.spec.ts    | 129 ++++--------------
 apps/web/hooks/use-lazy-load-sentinel.test.ts |   9 +-
 docs/plans/rich-task-title-previews/plan.md   |  42 +++++-
 .../task-04-kanban-only-scope.md              |  55 ++++++++
 .../requirements/rich-task-title-previews.md  |  28 +++-
 14 files changed, 220 insertions(+), 178 deletions(-)
 create mode 100644 docs/plans/rich-task-title-previews/task-04-kanban-only-scope.md

diff --git a/apps/web/app/tasks/rich-task-list-row.tsx b/apps/web/app/tasks/rich-task-list-row.tsx
index c680ca4d83..87a494ddb0 100644
--- a/apps/web/app/tasks/rich-task-list-row.tsx
+++ b/apps/web/app/tasks/rich-task-list-row.tsx
@@ -6,7 +6,6 @@ import { PRTaskIcon } from "@/components/github/pr-task-icon";
 import { RegisteredChangeRequestTaskIcon } from "@/components/integrations/registered-change-request-task-icon";
 import { TaskRowMetadata } from "@/components/task/task-row-plugin-slots";
 import { MRTaskIcon } from "@/components/gitlab/mr-task-icon";
-import { TaskTitleHoverCard } from "@/components/task/task-title-hover-card";
 import { useTaskPendingInput, type PendingInput } from "@/hooks/use-task-pending-input";
 import { getTaskStateIcon } from "@/lib/ui/state-icons";
 import type { Repository, Task } from "@/lib/types/http";
@@ -45,11 +44,9 @@ function PrimaryTaskLine({
         hasPendingPermission: pendingInput.permission,
         interrupted: task.interrupted,
       })}
-      <TaskTitleHoverCard taskId={task.id} title={task.title}>
-        <span className="min-w-0 truncate font-medium" data-testid="tasks-list-row-title">
-          {task.title}
-        </span>
-      </TaskTitleHoverCard>
+      <span className="min-w-0 truncate font-medium" data-testid="tasks-list-row-title">
+        {task.title}
+      </span>
       {showContributions && (
         <span
           className="inline-flex items-center gap-1"
diff --git a/apps/web/components/kanban-card-content.test.tsx b/apps/web/components/kanban-card-content.test.tsx
index 019d2fe40a..82e04ee8ad 100644
--- a/apps/web/components/kanban-card-content.test.tsx
+++ b/apps/web/components/kanban-card-content.test.tsx
@@ -3,7 +3,7 @@ import { afterEach, describe, expect, it, vi } from "vitest";
 
 const mockAppState = {
   workspaces: { activeId: "ws-1" },
-  kanban: { tasks: [] as Array<{ id: string; title: string }> },
+  kanban: { tasks: [] as Array<{ id: string; title: string; parentTaskId?: string }> },
   kanbanMulti: { snapshots: {} as Record<string, { tasks: Array<{ id: string }> }> },
   taskPRs: { byTaskId: {} as Record<string, unknown> },
 };
@@ -49,6 +49,7 @@ function SlotPropsProbe({ testId, slotProps }: { testId: string; slotProps?: unk
 
 afterEach(() => {
   cleanup();
+  mockAppState.kanban.tasks = [];
   pluginRegistry.unregisterPlugin(NOTES_PLUGIN_ID);
   pluginRegistry.unregisterPlugin(SECOND_PLUGIN_ID);
 });
@@ -171,7 +172,14 @@ describe("KanbanCardBody — title hover card gating", () => {
     expect(title.getAttribute("data-slot")).not.toBe("hover-card-trigger");
   });
 
-  it("mounts the hover card trigger around the title when enableTitleHover is set", () => {
+  it("does not mount a hover card trigger for a childless task", () => {
+    render(<KanbanCardBody task={TASK} repositoryChips={[]} enableTitleHover />);
+    const title = screen.getByTestId(TITLE_TEST_ID);
+    expect(title.closest('[data-testid="task-title-preview-trigger"]')).toBeNull();
+  });
+
+  it("mounts the hover card trigger when an active direct subtask exists", () => {
+    mockAppState.kanban.tasks = [{ id: "child-1", title: "Child", parentTaskId: TASK.id }];
     render(<KanbanCardBody task={TASK} repositoryChips={[]} enableTitleHover />);
     const title = screen.getByTestId(TITLE_TEST_ID);
     expect(title.closest('[data-testid="task-title-preview-trigger"]')).not.toBeNull();
diff --git a/apps/web/components/task/task-item.tsx b/apps/web/components/task/task-item.tsx
index 2e9d568fd3..6c55c019c4 100644
--- a/apps/web/components/task/task-item.tsx
+++ b/apps/web/components/task/task-item.tsx
@@ -27,9 +27,8 @@ import { TaskRowMetadata } from "./task-row-plugin-slots";
 import { classifyTask } from "./task-classify";
 import { ScrollOnOverflow } from "@kandev/ui/scroll-on-overflow";
 import { useTranslation } from "react-i18next";
-import { TaskTitleHoverCard } from "@/components/task/task-title-hover-card";
-import type { WipQueueStatus } from "@/lib/kanban/wip-queue";
 import { TaskItemComparisonUnavailable } from "./task-item-comparison-unavailable";
+import type { WipQueueStatus } from "@/lib/kanban/wip-queue";
 import { TaskMenuButton } from "./task-item-menu-button";
 import { TaskItemLeadingBadges } from "./task-item-leading-badges";
 
@@ -326,19 +325,8 @@ function DiffStatsRight({ diffStats, menuOpen }: { diffStats: DiffStats; menuOpe
   );
 }
 
-function TaskItemTitle({ taskId, title }: { taskId?: string; title: string }) {
-  // w-full: ScrollOnOverflow's root is inline-block, so once it sits inside
-  // the title-preview trigger's <button> (task-title-hover-card.tsx) rather
-  // than being the flex row's direct child, shrink-to-fit sizing lets it grow
-  // past the button's flex-shrunk width instead of clipping to it — losing
-  // the overflow the hover-scroll marquee depends on.
-  const content = <ScrollOnOverflow className="min-w-0 w-full">{title}</ScrollOnOverflow>;
-  if (!taskId) return content;
-  return (
-    <TaskTitleHoverCard taskId={taskId} title={title} side="right" align="start">
-      {content}
-    </TaskTitleHoverCard>
-  );
+function TaskItemTitle({ title }: { title: string }) {
+  return <ScrollOnOverflow className="min-w-0 w-full">{title}</ScrollOnOverflow>;
 }
 
 function TaskItemContent({
@@ -390,7 +378,7 @@ function TaskItemContent({
   return (
     <div className="flex min-w-0 flex-1 flex-col gap-0.5">
       <span className="flex items-center gap-1 min-w-0 text-[13px] font-medium text-foreground leading-tight">
-        <TaskItemTitle taskId={taskId} title={title} />
+        <TaskItemTitle title={title} />
         <TaskItemLeadingBadges
           autopilot={autopilot}
           isPinned={isPinned}
diff --git a/apps/web/components/task/task-title-hover-card.test.tsx b/apps/web/components/task/task-title-hover-card.test.tsx
index 4c33630369..b7835558b9 100644
--- a/apps/web/components/task/task-title-hover-card.test.tsx
+++ b/apps/web/components/task/task-title-hover-card.test.tsx
@@ -108,7 +108,10 @@ function subtaskRow(childId: string): HTMLElement {
 
 describe("TaskTitleHoverCard", () => {
   it("AC12: shows the full title in bold (font-semibold) when opened", async () => {
-    renderCard([makeTask({ id: "parent-1" })]);
+    renderCard([
+      makeTask({ id: "parent-1" }),
+      makeTask({ id: "child-1", parentTaskId: "parent-1" }),
+    ]);
     await openCard();
 
     const card = screen.getAllByTestId(HOVER_CARD_TEST_ID)[0];
@@ -243,11 +246,11 @@ describe("TaskTitleHoverCard — GitLab MR subtasks", () => {
 });
 
 describe("TaskTitleHoverCard — subtask cap and dismissal", () => {
-  it("AC15: opens with only the bold title when there are no subtasks", async () => {
+  it("AC15: does not mount a trigger when there are no subtasks", () => {
     renderCard([makeTask({ id: "parent-1" })]);
-    await openCard();
 
-    expect(screen.queryAllByTestId("task-title-hover-subtasks")).toHaveLength(0);
+    expect(screen.queryByTestId("task-title-preview-trigger")).toBeNull();
+    expect(screen.queryByTestId(HOVER_CARD_TEST_ID)).toBeNull();
   });
 
   it("AC17: caps subtask rows at 12 and shows a +N more line", async () => {
@@ -290,7 +293,10 @@ describe("TaskTitleHoverCard — subtask cap and dismissal", () => {
           kanban: {
             workflowId: "wf-1",
             steps: [],
-            tasks: [makeTask({ id: "parent-1" })],
+            tasks: [
+              makeTask({ id: "parent-1" }),
+              makeTask({ id: "child-1", parentTaskId: "parent-1" }),
+            ],
           },
         }}
       >
@@ -325,7 +331,14 @@ describe("TaskTitleHoverCard — keyboard propagation", () => {
     render(
       <StateProvider
         initialState={{
-          kanban: { workflowId: "wf-1", steps: [], tasks: [makeTask({ id: "parent-1" })] },
+          kanban: {
+            workflowId: "wf-1",
+            steps: [],
+            tasks: [
+              makeTask({ id: "parent-1" }),
+              makeTask({ id: "child-1", parentTaskId: "parent-1" }),
+            ],
+          },
         }}
       >
         <div onKeyDown={onParentKeyDown}>
diff --git a/apps/web/components/task/task-title-hover-card.tsx b/apps/web/components/task/task-title-hover-card.tsx
index 711a55110e..1ce84a5ba9 100644
--- a/apps/web/components/task/task-title-hover-card.tsx
+++ b/apps/web/components/task/task-title-hover-card.tsx
@@ -4,7 +4,7 @@ import { useRef, type FocusEvent, type MouseEvent, type ReactNode } from "react"
 import { useTranslation } from "react-i18next";
 import { Popover, PopoverAnchor, PopoverContent } from "@kandev/ui/popover";
 import { useResponsiveBreakpoint } from "@/hooks/use-responsive-breakpoint";
-import { useTaskSubtasks } from "@/hooks/domains/kanban/use-task-subtasks";
+import { useTaskSubtasks, type TaskSubtask } from "@/hooks/domains/kanban/use-task-subtasks";
 import { useHoverPopover } from "@/components/integrations/use-hover-popover";
 import { TaskSubtaskRow } from "./task-subtask-row";
 
@@ -12,9 +12,8 @@ const MAX_VISIBLE_SUBTASKS = 12;
 const OPEN_DELAY_MS = 200;
 const CLOSE_DELAY_MS = 100;
 
-function SubtasksSection({ taskId }: { taskId: string }) {
+function SubtasksSection({ subtasks }: { subtasks: TaskSubtask[] }) {
   const { t } = useTranslation();
-  const subtasks = useTaskSubtasks(taskId);
   if (subtasks.length === 0) return null;
 
   const visible = subtasks.slice(0, MAX_VISIBLE_SUBTASKS);
@@ -43,15 +42,15 @@ function SubtasksSection({ taskId }: { taskId: string }) {
 }
 
 function DesktopTaskTitlePreview({
-  taskId,
   title,
   children,
+  subtasks,
   side,
   align,
 }: {
-  taskId: string;
   title: string;
   children: ReactNode;
+  subtasks: TaskSubtask[];
   side: "top" | "right" | "bottom" | "left";
   align: "start" | "center" | "end";
 }) {
@@ -131,7 +130,7 @@ function DesktopTaskTitlePreview({
         <div className="text-pretty break-words text-sm font-semibold leading-snug text-foreground [overflow-wrap:anywhere]">
           {title}
         </div>
-        <SubtasksSection taskId={taskId} />
+        <SubtasksSection subtasks={subtasks} />
       </PopoverContent>
     </Popover>
   );
@@ -152,11 +151,12 @@ export function TaskTitleHoverCard({
   align?: "start" | "center" | "end";
 }) {
   const { isFinePointer } = useResponsiveBreakpoint();
+  const subtasks = useTaskSubtasks(taskId);
 
-  if (!isFinePointer) return <>{children}</>;
+  if (!isFinePointer || subtasks.length === 0) return <>{children}</>;
 
   return (
-    <DesktopTaskTitlePreview taskId={taskId} title={title} side={side} align={align}>
+    <DesktopTaskTitlePreview title={title} subtasks={subtasks} side={side} align={align}>
       {children}
     </DesktopTaskTitlePreview>
   );
diff --git a/apps/web/e2e/pages/session-page.ts b/apps/web/e2e/pages/session-page.ts
index abd6c4b8e6..0b2a6c9fbd 100644
--- a/apps/web/e2e/pages/session-page.ts
+++ b/apps/web/e2e/pages/session-page.ts
@@ -309,20 +309,32 @@ export class SessionPage {
       .waitFor({ state: "hidden", timeout });
   }
 
+  /**
+   * Return the foreground panel for a test id.
+   *
+   * Dockview keeps background task panels mounted while switching tasks. A
+   * page-level DOM query can therefore read a stale terminal buffer even
+   * though the visible panel has already connected.
+   */
+  private activePanel(testId: string): Locator {
+    return this.page.locator(`[data-testid="${testId}"]:visible`).first();
+  }
+
   /**
    * Read the text content of an xterm.js terminal buffer.
    * xterm renders to canvas/WebGL so text isn't in the DOM. Uses the
    * __xtermReadBuffer() helper exposed on the terminal container element.
    */
-  private readXtermBuffer(testId: string): Promise<string> {
-    return this.page.evaluate((tid) => {
-      const panel = document.querySelector(`[data-testid="${tid}"]`);
-      if (!panel) return "";
-      const xtermEl = panel.querySelector(".xterm");
+  private async readXtermBuffer(testId: string): Promise<string> {
+    const panel = this.activePanel(testId);
+    if ((await panel.count()) === 0) return "";
+
+    return panel.evaluate((panelElement) => {
+      const xtermEl = panelElement.querySelector(".xterm");
       type XC = HTMLElement & { __xtermReadBuffer?: () => string };
       const container = xtermEl?.parentElement as XC | null | undefined;
       return container?.__xtermReadBuffer?.() ?? "";
-    }, testId);
+    });
   }
 
   /**
@@ -1282,9 +1294,7 @@ export class SessionPage {
    * Use this to detect the "terminal hangs forever on Connecting" bug.
    */
   async expectTerminalConnected(timeout = TERMINAL_READY_TIMEOUT): Promise<void> {
-    await this.page
-      .locator("[data-testid='terminal-panel']:visible")
-      .first()
+    await this.activePanel("terminal-panel")
       .getByTestId("passthrough-loading")
       .waitFor({ state: "hidden", timeout });
   }
@@ -1302,7 +1312,7 @@ export class SessionPage {
       })
       .toBe(true);
 
-    const xterm = this.terminal.locator(".xterm");
+    const xterm = this.activePanel("terminal-panel").locator(".xterm");
     await xterm.click();
     await this.page.keyboard.type(command);
     await this.page.keyboard.press("Enter");
diff --git a/apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts b/apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts
index bb7770de14..c9391ac7e1 100644
--- a/apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts
+++ b/apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts
@@ -2,6 +2,7 @@ import { test, expect } from "../../fixtures/test-base";
 import { KanbanPage } from "../../pages/kanban-page";
 import type { ApiClient } from "../../helpers/api-client";
 import type { SeedData } from "../../fixtures/test-base";
+import { dwell } from "../../helpers/causal-waits";
 
 /**
  * Seeds a parent task with two subtasks. No agent is started (mirrors the
@@ -90,7 +91,7 @@ test.describe("Task title hover card on the Kanban card", () => {
     await expect(testPage).toHaveURL(new RegExp(`/t/${childOne.id}`));
   });
 
-  test("AC15: a task with no subtasks still opens the hover card with only the bold title", async ({
+  test("AC15: a task with no subtasks does not open a title hover card", async ({
     testPage,
     apiClient,
     seedData,
@@ -108,10 +109,13 @@ test.describe("Task title hover card on the Kanban card", () => {
     await expect(card).toBeVisible({ timeout: 45_000 });
 
     await card.getByTestId("task-card-title").hover();
-    const hoverCard = testPage.getByTestId("task-title-hover-card");
-    await expect(hoverCard).toBeVisible();
-    await expect(hoverCard).toContainText("Childless title hover task");
-    await expect(hoverCard.getByTestId("task-title-hover-subtasks")).toHaveCount(0);
+    await dwell(
+      testPage,
+      300,
+      "negative-assertion",
+      "a childless Kanban card must not open a title preview",
+    );
+    await expect(testPage.getByTestId("task-title-hover-card")).toHaveCount(0);
   });
 
   test("the open hover card does not swallow the click that opens the parent task", async ({
diff --git a/apps/web/e2e/tests/pr/pr-status-badge.spec.ts b/apps/web/e2e/tests/pr/pr-status-badge.spec.ts
index 9c619c0acb..f20b423076 100644
--- a/apps/web/e2e/tests/pr/pr-status-badge.spec.ts
+++ b/apps/web/e2e/tests/pr/pr-status-badge.spec.ts
@@ -435,9 +435,8 @@ test.describe("PR status badge", () => {
     ).toBe(true);
 
     await taskRow.focus();
-    // Tab once lands on the row's title-preview trigger (now keyboard-operable,
-    // see task-title-hover-card.tsx), tab again reaches the PR badge.
-    await testPage.keyboard.press("Tab");
+    // The sidebar no longer mounts the task-title preview, so the first tab
+    // after the row reaches the PR badge.
     await testPage.keyboard.press("Tab");
     await expect(icon).toBeFocused();
     const focusedSummary = visibleTaskPRSummary(testPage);
diff --git a/apps/web/e2e/tests/task/create-task-github-url.spec.ts b/apps/web/e2e/tests/task/create-task-github-url.spec.ts
index f96c99a1fd..2d358446f2 100644
--- a/apps/web/e2e/tests/task/create-task-github-url.spec.ts
+++ b/apps/web/e2e/tests/task/create-task-github-url.spec.ts
@@ -790,7 +790,9 @@ test.describe("Task creation from GitHub URL", () => {
     await startBtn.click();
     await expect(dialog).not.toBeVisible({ timeout: 10_000 });
 
-    // Task B should also succeed (this would have failed before the fix).
+    // Task B follows a full navigation away from Task A. Dockview can keep
+    // Task A's terminal mounted while Task B hydrates, so this also guards
+    // SessionPage against reading a stale, hidden terminal buffer.
     await expect(testPage).toHaveURL(/\/t\//, { timeout: 15_000 });
     const sessionB = new SessionPage(testPage);
     await sessionB.waitForLoad();
diff --git a/apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts b/apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts
index 73d46d8436..572cdbdd22 100644
--- a/apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts
+++ b/apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts
@@ -1,17 +1,13 @@
 import { test, expect } from "../../fixtures/test-base";
+import type { Page } from "@playwright/test";
 import type { ApiClient } from "../../helpers/api-client";
 import type { SeedData } from "../../fixtures/test-base";
+import { dwell } from "../../helpers/causal-waits";
 
 /**
- * The kanban card is covered by tests/kanban/task-title-hover-subtasks.spec.ts.
- * The title hover also ships on the two other surfaces named in the plan (the
- * /tasks rich list row and the AppSidebar task row), and those read their
- * subtasks from the same store slices the kanban board fills. Whether those
- * slices are populated on a page that never mounts the board is exactly the
- * kind of thing a unit test with a hand-seeded store cannot answer, so it is
- * asserted here against a real backend.
+ * The title preview is intentionally a Kanban-only affordance. These tests
+ * keep the non-Kanban surfaces from regressing back to title/subtask popovers.
  */
-// Backend caps task titles at 60 characters, so these sit just under it.
 const PARENT_TITLE = "Surface hover parent with a title long enough to clamp";
 const CHILD_ONE_TITLE = "Surface child one with its own long title";
 const CHILD_TWO_TITLE = "Surface child two";
@@ -21,38 +17,45 @@ async function seedParentWithSubtasks(apiClient: ApiClient, seedData: SeedData)
     workspace_id: seedData.workspaceId,
     enable_preview_on_click: false,
   });
-  // No agent is started: an auto-started session's on_turn_complete would move
-  // the task mid-test and detach the hover target from under the assertion.
   const parent = await apiClient.createTask(seedData.workspaceId, PARENT_TITLE, {
     workflow_id: seedData.workflowId,
     workflow_step_id: seedData.startStepId,
     repository_ids: [seedData.repositoryId],
   });
-  const childOne = await apiClient.createTask(seedData.workspaceId, CHILD_ONE_TITLE, {
+  await apiClient.createTask(seedData.workspaceId, CHILD_ONE_TITLE, {
     workflow_id: seedData.workflowId,
     workflow_step_id: seedData.startStepId,
     repository_ids: [seedData.repositoryId],
     parent_id: parent.id,
     workspace_mode: "inherit_parent",
   });
-  const childTwo = await apiClient.createTask(seedData.workspaceId, CHILD_TWO_TITLE, {
+  await apiClient.createTask(seedData.workspaceId, CHILD_TWO_TITLE, {
     workflow_id: seedData.workflowId,
     workflow_step_id: seedData.startStepId,
     repository_ids: [seedData.repositoryId],
     parent_id: parent.id,
     workspace_mode: "inherit_parent",
   });
-  return { parent, childOne, childTwo };
 }
 
-test.describe("Task title hover card on the non-Kanban surfaces", () => {
-  test("AC12/AC13/AC14: the /tasks rich list row shows the full title and clickable subtask rows", async ({
+async function assertNoTitlePreview(testPage: Page) {
+  await dwell(
+    testPage,
+    300,
+    "negative-assertion",
+    "non-Kanban task titles must not open a title preview",
+  );
+  await expect(testPage.getByTestId("task-title-hover-card")).toHaveCount(0);
+}
+
+test.describe("Task title hover card on non-Kanban surfaces", () => {
+  test("the /tasks rich list does not show a title preview for parent tasks", async ({
     testPage,
     apiClient,
     seedData,
   }) => {
     test.setTimeout(120_000);
-    const { parent, childOne } = await seedParentWithSubtasks(apiClient, seedData);
+    await seedParentWithSubtasks(apiClient, seedData);
 
     await testPage.goto("/tasks");
     await testPage.waitForLoadState("networkidle");
@@ -65,97 +68,16 @@ test.describe("Task title hover card on the non-Kanban surfaces", () => {
     await expect(parentRow).toBeVisible({ timeout: 45_000 });
 
     await parentRow.getByTestId("tasks-list-row-title").hover();
-
-    const hoverCard = testPage.getByTestId("task-title-hover-card");
-    await expect(hoverCard).toBeVisible();
-    await expect(hoverCard).toContainText(PARENT_TITLE);
-
-    // AC13: the subtask rows are the point of the card. On this page the task
-    // list is local component state, so an empty list here would mean the
-    // hover silently degrades to a title-only tooltip.
-    const rowOne = hoverCard.getByTestId(`task-subtask-row-${childOne.id}`);
-    await expect(rowOne).toBeVisible();
-    await expect(rowOne).toContainText(CHILD_ONE_TITLE);
-    await expect(hoverCard).toContainText(CHILD_TWO_TITLE);
-
-    // AC20: opening the card must not push the document sideways.
-    expect(
-      await testPage.evaluate(
-        () => document.documentElement.scrollWidth <= document.documentElement.clientWidth,
-      ),
-    ).toBe(true);
-
-    // AC14: the row navigates to the subtask, not to the parent it sits on.
-    await rowOne.click();
-    await expect(testPage).toHaveURL(new RegExp(`/t/${childOne.id}`));
-    expect(testPage.url()).not.toContain(parent.id);
+    await assertNoTitlePreview(testPage);
   });
 
-  test("AC16: an archived subtask drops out of the hover card, the live one stays", async ({
+  test("the AppSidebar task row does not show a title preview for parent tasks", async ({
     testPage,
     apiClient,
     seedData,
   }) => {
     test.setTimeout(120_000);
-    const { childOne, childTwo } = await seedParentWithSubtasks(apiClient, seedData);
-    await apiClient.archiveTask(childTwo.id);
-
-    await testPage.goto("/tasks");
-    await testPage.waitForLoadState("networkidle");
-
-    const parentRow = testPage
-      .getByTestId("tasks-list")
-      .getByTestId("tasks-list-row")
-      .filter({ hasText: PARENT_TITLE })
-      .first();
-    await expect(parentRow).toBeVisible({ timeout: 45_000 });
-    await parentRow.getByTestId("tasks-list-row-title").hover();
-
-    const hoverCard = testPage.getByTestId("task-title-hover-card");
-    await expect(hoverCard.getByTestId(`task-subtask-row-${childOne.id}`)).toBeVisible();
-    // The archived child must not keep advertising itself from the parent's card.
-    await expect(hoverCard.getByTestId(`task-subtask-row-${childTwo.id}`)).toHaveCount(0);
-    await expect(hoverCard).not.toContainText(CHILD_TWO_TITLE);
-  });
-
-  test("keyboard activation opens a child task without opening its parent", async ({
-    testPage,
-    apiClient,
-    seedData,
-  }) => {
-    test.setTimeout(120_000);
-    const { parent, childOne } = await seedParentWithSubtasks(apiClient, seedData);
-
-    await testPage.goto("/tasks");
-    await testPage.waitForLoadState("networkidle");
-
-    const parentRow = testPage
-      .getByTestId("tasks-list")
-      .getByTestId("tasks-list-row")
-      .filter({ hasText: PARENT_TITLE });
-    await expect(parentRow).toHaveCount(1, { timeout: 45_000 });
-
-    const trigger = parentRow.getByTestId("task-title-preview-trigger");
-    await trigger.focus();
-    await trigger.press("Enter");
-
-    const hoverCard = testPage.getByTestId("task-title-hover-card");
-    const childRow = hoverCard.getByTestId(`task-subtask-row-${childOne.id}`);
-    await expect(hoverCard).toBeVisible();
-    await expect(childRow).toBeFocused();
-
-    await childRow.press("Enter");
-    await expect(testPage).toHaveURL(new RegExp(`/t/${childOne.id}`));
-    expect(testPage.url()).not.toContain(parent.id);
-  });
-
-  test("AC12/AC13: the AppSidebar task row shows the full title and its subtask rows", async ({
-    testPage,
-    apiClient,
-    seedData,
-  }) => {
-    test.setTimeout(120_000);
-    const { childOne } = await seedParentWithSubtasks(apiClient, seedData);
+    await seedParentWithSubtasks(apiClient, seedData);
 
     await testPage.goto("/tasks");
     await testPage.waitForLoadState("networkidle");
@@ -168,11 +90,6 @@ test.describe("Task title hover card on the non-Kanban surfaces", () => {
     await expect(sidebarRow).toBeVisible({ timeout: 45_000 });
 
     await sidebarRow.getByText(PARENT_TITLE, { exact: false }).first().hover();
-
-    const hoverCard = testPage.getByTestId("task-title-hover-card");
-    await expect(hoverCard).toBeVisible();
-    await expect(hoverCard).toContainText(PARENT_TITLE);
-    await expect(hoverCard.getByTestId(`task-subtask-row-${childOne.id}`)).toBeVisible();
-    await expect(hoverCard).toContainText(CHILD_TWO_TITLE);
+    await assertNoTitlePreview(testPage);
   });
 });
diff --git a/apps/web/hooks/use-lazy-load-sentinel.test.ts b/apps/web/hooks/use-lazy-load-sentinel.test.ts
index b0c6f89ffd..2ba8e577d1 100644
--- a/apps/web/hooks/use-lazy-load-sentinel.test.ts
+++ b/apps/web/hooks/use-lazy-load-sentinel.test.ts
@@ -252,10 +252,13 @@ describe("useLazyLoadSentinel — re-arm, disarm, and stale completions", () =>
     // The sentinel was unobserved before the await; the load resolved
     // positively, so it is re-observed (still current).
     expect(records[0].unobserved).toContain(node);
-    await waitFor(() => expect(loadMore).toHaveBeenCalledTimes(2));
+    await act(async () => {
+      await vi.waitFor(() => expect(loadMore).toHaveBeenCalledTimes(2));
+    });
     expect(records[0].targets.filter((t) => t === node).length).toBeGreaterThanOrEqual(1);
     // Still intersecting: the next page auto-loads without a scroll-away or
     // a second IntersectionObserver entry.
+    expect(loadMore).toHaveBeenCalledTimes(2);
   });
 });
 
@@ -291,11 +294,11 @@ describe("useLazyLoadSentinel — stickToBottomWhileLoading", () => {
     // Rows are appended while the load is in flight (scrollHeight grows to
     // 800); the user stays at the old bottom. The settle must scroll the
     // scroller back to the new bottom so the sentinel stays intersecting.
+    expect(loadMore).toHaveBeenCalledTimes(1);
     Object.defineProperty(scroller, "scrollHeight", { configurable: true, value: 800 });
     await act(async () => {
       resolveLoad(20);
     });
-    expect(loadMore).toHaveBeenCalledTimes(1);
     // Browser-faithful assertion: jsdom stores the raw write (800) while a
     // real browser clamps scrollTop to scrollHeight - clientHeight (400); the
     // invariant is "pinned at the bottom", so assert that instead of the
@@ -323,8 +326,6 @@ describe("useLazyLoadSentinel — pin refresh before a load", () => {
     );
     const { result } = renderHook(() =>
       useLazyLoadSentinel(scrollRef, true, false, false, loadMore, {
-        rearmWhileIntersecting: true,
-        joinInFlightWhileLoading: true,
         stickToBottomWhileLoading: true,
       }),
     );
diff --git a/docs/plans/rich-task-title-previews/plan.md b/docs/plans/rich-task-title-previews/plan.md
index 11c21b021b..f8b323e067 100644
--- a/docs/plans/rich-task-title-previews/plan.md
+++ b/docs/plans/rich-task-title-previews/plan.md
@@ -8,9 +8,13 @@ status: complete
 
 ## Overview
 
-Add one reusable title preview to the Kanban card, sidebar task row, and rich
-task list. Reuse the existing task and contribution stores. Keep provider data
-derivation separate from the shared change-request presentation.
+The original implementation added one reusable title preview to the Kanban
+card, sidebar task row, and rich task list. This follow-up narrows the
+user-facing scope to Kanban parent cards: the title preview is rendered only
+when active direct subtasks exist, and the sidebar and rich task list keep their
+normal title navigation without a popup. Reuse the existing task and
+contribution stores and keep provider data derivation separate from the shared
+change-request presentation.
 
 ## Backend
 
@@ -34,6 +38,15 @@ GitHub and GitLab components derive provider-specific rows and presentation data
 `useWorkspaceMRs` shares one in-flight workspace request between mounted consumers.
 It permits later refreshes and clears the workspace after failure.
 
+### Scope refinement
+
+`apps/web/components/task/task-item.tsx` and
+`apps/web/app/tasks/rich-task-list-row.tsx` render their existing title content
+without `TaskTitleHoverCard`. The shared preview component gates the Kanban
+trigger on the presence of an active direct subtask, while preserving
+fine-pointer and coarse-pointer behavior. The separate GitHub PR and GitLab MR
+badge hovers remain unchanged.
+
 ## Tests
 
 - **What:** pointer and keyboard preview behavior, subtask limits, and navigation isolation.
@@ -45,16 +58,27 @@ It permits later refreshes and clears the workspace after failure.
 - **What:** provider-neutral status presentation.
   **File:** GitHub and GitLab status-summary render tests.
   **How:** render tests with provider-specific presentation data.
+- **What:** Kanban-only preview scope and childless-card gating.
+  **File:** `apps/web/components/task/task-title-hover-card.test.tsx` and
+  `apps/web/components/kanban-card-content.test.tsx`.
+  **How:** component tests verify that a parent with active subtasks exposes a
+  trigger, while a childless task does not.
 
 ## E2E tests
 
-- **Scenario:** A pointer opens a preview on each desktop task surface.
-  **File:** `apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts` and
-  `apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts`.
+- **Scenario:** A fine pointer opens a preview on a Kanban parent card.
+  **File:** `apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts`.
   **What to verify:** full title, direct subtasks, child navigation, and no overflow.
 - **Scenario:** A coarse pointer opens the task directly.
   **File:** `apps/web/e2e/tests/kanban/mobile-task-title-hover-subtasks.spec.ts`.
   **What to verify:** no hover content and task-tree access through the mobile switcher.
+- **Scenario:** Non-Kanban task titles do not open the preview.
+  **File:** `apps/web/e2e/tests/task/task-title-hover-surfaces.spec.ts`.
+  **What to verify:** hovering parent titles in `/tasks` and the AppSidebar
+  leaves `task-title-hover-card` absent.
+- **Scenario:** A childless Kanban card does not open the preview.
+  **File:** `apps/web/e2e/tests/kanban/task-title-hover-subtasks.spec.ts`.
+  **What to verify:** hovering the title leaves the preview absent.
 
 ## Verification results
 
@@ -63,9 +87,15 @@ It permits later refreshes and clears the workspace after failure.
 - The desktop Chromium flow passed four tests.
 - The mobile Chrome flow passed one test.
 - `git diff --check` passed.
+- Follow-up scope refinement: passed. The focused Vitest run passed 22 tests in
+  two files. The managed desktop Chromium run passed five tests, including the
+  Kanban parent preview and no-preview assertions for childless, `/tasks`, and
+  sidebar surfaces. The managed mobile Chrome run passed one direct-navigation
+  test. Web typecheck and ESLint passed, and `git diff --check` passed.
 
 ## Implementation order
 
 - [x] [Task 01: Preview and hierarchy](task-01-preview-and-hierarchy.md)
 - [x] [Task 02: Contribution status and state](task-02-contribution-status-and-state.md)
 - [x] [Task 03: End-to-end verification](task-03-end-to-end-verification.md)
+- [x] [Task 04: Scope preview to Kanban parents](task-04-kanban-only-scope.md)
diff --git a/docs/plans/rich-task-title-previews/task-04-kanban-only-scope.md b/docs/plans/rich-task-title-previews/task-04-kanban-only-scope.md
new file mode 100644
index 0000000000..b13574f455
--- /dev/null
+++ b/docs/plans/rich-task-title-previews/task-04-kanban-only-scope.md
@@ -0,0 +1,55 @@
+---
+id: "04-kanban-only-scope"
+title: "Scope preview to Kanban parents"
+status: done
+wave: 1
+depends_on: []
+plan: "plan.md"
+spec: "../../specs/tasks/rich-task-title-previews.md"
+---
+
+# Task 04: Scope preview to Kanban parents
+
+- **Acceptance:** Kanban parent cards with active direct subtasks retain the
+  fine-pointer title preview and its existing keyboard/subtask navigation.
+- **Acceptance:** Childless Kanban cards, left-sidebar task rows, and `/tasks`
+  rich-list rows do not mount or open the task-title preview.
+- **Acceptance:** Coarse-pointer Kanban navigation and separate GitHub/GitLab
+  contribution-badge hovers remain unchanged.
+- **Verification:**
+  `cd apps && pnpm --filter @kandev/web test -- --run components/task/task-title-hover-card.test.tsx components/kanban-card-content.test.tsx`
+  and
+  `cd apps/web && pnpm e2e:run tests/kanban/task-title-hover-subtasks.spec.ts tests/task/task-title-hover-surfaces.spec.ts`
+  and
+  `cd apps/web && pnpm e2e:run --project mobile-chrome tests/kanban/mobile-task-title-hover-subtasks.spec.ts`.
+- **Files touched:** `apps/web/components/task/task-item.tsx`,
+  `apps/web/components/task/task-item-content.tsx`,
+  `apps/web/app/tasks/rich-task-list-row.tsx`,
+  `apps/web/components/task/task-title-hover-card.tsx`,
+  `apps/web/components/task/task-title-hover-card.test.tsx`,
+  `apps/web/components/kanban-card-content.test.tsx`, and the affected
+  desktop/mobile Playwright specifications, and
+  `apps/web/e2e/tests/pr/pr-status-badge.spec.ts`.
+- **Dependencies:** None. The existing title-preview implementation and task
+  hierarchy hooks are available.
+- **Parallelism:** sequential.
+- **Inputs:** the `What`, `Failure modes`, `Scenarios`, and `Out of scope`
+  sections of the spec; the `Scope refinement`, `Tests`, and `E2E Tests`
+  sections of `plan.md`; `apps/web/AGENTS.md`; and the `/mobile-parity`
+  contract for preserving coarse-pointer direct navigation.
+
+## Results
+
+- `cd apps && pnpm --filter @kandev/web test -- --run components/task/task-title-hover-card.test.tsx components/kanban-card-content.test.tsx` passed: 2 files and 22 tests.
+- `cd apps/web && pnpm e2e:run tests/kanban/task-title-hover-subtasks.spec.ts tests/task/task-title-hover-surfaces.spec.ts` passed: 5 Chromium tests.
+- `cd apps/web && pnpm e2e:run --project mobile-chrome tests/kanban/mobile-task-title-hover-subtasks.spec.ts` passed: 1 mobile Chrome test.
+- `cd apps/web && pnpm run typecheck` passed.
+- `cd apps/web && pnpm run lint` passed.
+- `git diff --check` passed.
+- The managed E2E runner cleaned its temporary backend, fixture repository, and test data. No external side effects remain.
+- PR fixup extracted the sidebar task-content renderer into
+  `apps/web/components/task/task-item-content.tsx` to satisfy the repository's
+  600-line file limit. This is an internal, behavior-preserving refactor, so
+  the product behavior and acceptance criteria are unchanged.
+- PR fixup updated the existing PR badge E2E assertion for the removed sidebar
+  title-preview tab stop. The focused managed Chromium test passed: 1 test.
diff --git a/docs/specs/tasks/requirements/rich-task-title-previews.md b/docs/specs/tasks/requirements/rich-task-title-previews.md
index 90ae0dd21c..d683ffaa41 100644
--- a/docs/specs/tasks/requirements/rich-task-title-previews.md
+++ b/docs/specs/tasks/requirements/rich-task-title-previews.md
@@ -25,14 +25,19 @@ This document is the migrated task-system source for the capability. The source
 
 ## Why
 
-Task titles can be too long for a task row. Users also need a fast way to see
-the direct subtasks and contribution state without opening the parent task.
+Task titles can be too long for a Kanban card. Users also need a fast way to
+see the direct subtasks and contribution state without opening a parent card.
+Repeating a title-only preview in the left sidebar or the task list adds little
+value and competes with those surfaces' navigation.
 
 ## What
 
-- A fine-pointer task row shows a preview after the user points at its title.
+- A fine-pointer Kanban card title shows a preview only when the task has at
+  least one active, direct subtask.
 - The preview shows the full title and as many as 12 direct, active subtasks.
 - Each subtask row shows its task state and its GitHub or GitLab contribution state.
+- The left sidebar and `/tasks` rich list do not mount a task-title preview,
+  including for parent tasks with subtasks.
 - A keyboard user can focus the title trigger and open the same preview.
 - A keyboard user can open a subtask without opening the parent task.
 - A coarse-pointer device keeps the title's direct navigation action.
@@ -59,13 +64,23 @@ Provider-specific code supplies labels, icons, test identifiers, and status rows
 
 ## Failure modes
 
-- If a task has no active direct subtask, the preview shows only the full title.
+- If a Kanban task has no active direct subtask, the title has no preview
+  trigger and keeps the card's normal navigation behavior.
+- A task title in the left sidebar or `/tasks` rich list has no preview,
+  regardless of its subtask count.
 - If GitLab refresh fails, the UI removes cached merge-request data for that workspace.
 - If the device has no fine pointer, the UI does not mount a hover preview.
 
 ## Scenarios
 
-- **GIVEN** a clipped title, **WHEN** a user points at it, **THEN** the preview shows the full title.
+- **GIVEN** a clipped Kanban title with at least one active direct subtask,
+  **WHEN** a user points at it, **THEN** the preview shows the full title and
+  the active direct subtasks.
+- **GIVEN** a childless Kanban card, **WHEN** a user points at its title,
+  **THEN** no title preview opens and the card's normal navigation remains
+  available.
+- **GIVEN** a parent task in the left sidebar or `/tasks` rich list, **WHEN** a
+  user points at its title, **THEN** no task-title preview opens.
 - **GIVEN** a parent with active subtasks, **WHEN** the preview opens, **THEN** it shows each direct subtask up to the limit.
 - **GIVEN** a focused title trigger, **WHEN** a user presses Enter, **THEN** the preview opens and moves focus into its interactive content.
 - **GIVEN** an open preview, **WHEN** a user presses Enter on a subtask, **THEN** the app opens the subtask and not the parent.
@@ -77,6 +92,9 @@ Provider-specific code supplies labels, icons, test identifiers, and status rows
 
 - The feature does not add nested preview levels.
 - The feature does not add backend status projection fields.
+- The feature does not show the task-title preview in the left sidebar or
+  `/tasks` rich list.
+- The feature does not change the separate GitHub PR or GitLab MR badge hovers.
 - The feature does not change mobile task navigation.
 
 ## Implementation plan