From 20aff6d9f643afe9abf8a048e68f019d049f5329 Mon Sep 17 00:00:00 2001
From: Luke Parker <10430890+Hona@users.noreply.github.com>
Date: Thu, 10 Sep 2026 11:14:49 +1000
Subject: [PATCH] fix(app): keep workspace tab views alive (#48255)

---
 .../session-workspace-tab-cycle.spec.ts       | 68 +++++++++++++++++++
 packages/app/src/session/timeline/cache.ts    | 15 +++-
 .../app/test-browser/timeline-cache.test.ts   | 31 ++++++++-
 3 files changed, 111 insertions(+), 3 deletions(-)
 create mode 100644 packages/app/e2e/regression/session-workspace-tab-cycle.spec.ts

diff --git a/packages/app/e2e/regression/session-workspace-tab-cycle.spec.ts b/packages/app/e2e/regression/session-workspace-tab-cycle.spec.ts
new file mode 100644
index 00000000000..fb123dba73d
--- /dev/null
+++ b/packages/app/e2e/regression/session-workspace-tab-cycle.spec.ts
@@ -0,0 +1,68 @@
+import { expect, test } from "@playwright/test"
+import type { OpenCodeEvent, SessionMessageInfo } from "@opencode/client/promise"
+import { mockOpenCodeServer } from "../utils/mock-server"
+import { fixture } from "../performance/timeline/session-timeline-stress.fixture"
+import { installStressSessionTabs, stressSessionHref } from "../performance/timeline/timeline-test-helpers"
+
+test.use({ viewport: { width: 1440, height: 900 }, serviceWorkers: "block" })
+
+test("keeps five loaded workspace tabs visible and reactive through repeated switches", async ({ page }, info) => {
+  const sessions = Array.from({ length: 5 }, (_, index) => ({
+    ...fixture.sessions[0]!,
+    id: `ses_workspace_cycle_${index}`,
+    directory: `${fixture.directory}/worktree-${index}`,
+    title: `Workspace session ${index}`,
+  }))
+  const events: OpenCodeEvent[] = []
+  await mockOpenCodeServer(page, {
+    ...fixture,
+    sessions,
+    pageMessages: (id) => ({
+      items: [
+        { id: `msg_user_${id}`, type: "user", text: `Prompt for ${id}`, time: { created: 1 } },
+        {
+          id: `msg_assistant_${id}`,
+          type: "assistant",
+          agent: "build",
+          model: { id: "claude-opus-4-6", providerID: "opencode" },
+          time: { created: 2, completed: 3 },
+          content: [{ type: "text", text: `Answer for ${id}` }],
+        },
+      ] satisfies SessionMessageInfo[],
+    }),
+    events: () => events.splice(0),
+  })
+  await page.route("**/api/location?*", (route) =>
+    route.fulfill({
+      json: {
+        directory: new URL(route.request().url()).searchParams.get("location[directory]"),
+        project: { id: fixture.project.id, directory: fixture.directory, canonical: fixture.directory },
+      },
+    }),
+  )
+  await installStressSessionTabs(page, { sessionIDs: sessions.map((session) => session.id) })
+  await page.goto(stressSessionHref(sessions[0]!.id))
+  await expect(page.getByText(`Answer for ${sessions[0]!.id}`, { exact: true })).toBeVisible()
+
+  for (const session of [...sessions.slice(1), ...sessions, ...sessions.toReversed()]) {
+    await page.locator(`[data-titlebar-tab-link][href="${stressSessionHref(session.id)}"]`).click()
+    await expect(page.locator(`[data-timeline-part-id="msg_assistant_${session.id}:text:0"]`)).toBeVisible()
+    await expect(page.locator("[data-timeline-virtual-content]")).toHaveCSS("visibility", "visible")
+  }
+  const active = sessions[0]!
+  events.push({
+    id: "evt_workspace_cycle_update",
+    created: 4,
+    type: "session.text.ended",
+    location: { directory: active.directory },
+    durable: { aggregateID: active.id, seq: 0, version: 1 },
+    data: {
+      sessionID: active.id,
+      assistantMessageID: `msg_assistant_${active.id}`,
+      ordinal: 0,
+      text: "Still receiving updates",
+    },
+  })
+  await expect(page.getByText("Still receiving updates", { exact: true })).toBeVisible()
+  await page.screenshot({ path: info.outputPath("workspace-tabs.png") })
+})
diff --git a/packages/app/src/session/timeline/cache.ts b/packages/app/src/session/timeline/cache.ts
index 6496fb01ac5..055a5a55e21 100644
--- a/packages/app/src/session/timeline/cache.ts
+++ b/packages/app/src/session/timeline/cache.ts
@@ -18,6 +18,7 @@ export function createTimelineCache(
   visible: Accessor<boolean>,
 ) {
   const owner = getOwner()
+  let workspace = untrack(session.identity.workspaceKey)
   const cache = createScopedCache(
     (key) =>
       createRoot((dispose) => {
@@ -51,8 +52,18 @@ export function createTimelineCache(
     { maxEntries: 16, dispose: (entry) => entry.dispose() },
   )
   onCleanup(cache.clear)
+  const syncWorkspace = (key: string) => {
+    if (workspace === key) return
+    workspace = key
+    cache.clear()
+  }
   // Providers follow the selected Location even while its history is loading.
   // Dispose detached views before their effects can read the new Location.
-  createComputed(on(session.identity.workspaceKey, cache.clear, { defer: true }))
-  return () => cache.get(session.identity.sessionKey()).value
+  createComputed(on(session.identity.workspaceKey, syncWorkspace, { defer: true }))
+  return () => {
+    // A tab's render can run before the workspace watcher in the same batch.
+    // Clear the old workspace here, and let that later watcher keep this view.
+    syncWorkspace(session.identity.workspaceKey())
+    return cache.get(session.identity.sessionKey()).value
+  }
 }
diff --git a/packages/app/test-browser/timeline-cache.test.ts b/packages/app/test-browser/timeline-cache.test.ts
index 3d3842eba21..af1b691107d 100644
--- a/packages/app/test-browser/timeline-cache.test.ts
+++ b/packages/app/test-browser/timeline-cache.test.ts
@@ -1,6 +1,6 @@
 import { expect, test } from "bun:test"
 import type { SessionMessageInfo } from "@opencode/client/promise"
-import { createMemo, createRoot, onCleanup } from "solid-js"
+import { batch, createMemo, createRoot, onCleanup } from "solid-js"
 import { createStore } from "solid-js/store"
 import { ServerScope, SessionRouteKey, SessionStateKey } from "../src/runtime/server/scope"
 import { createTimelineCache } from "../src/session/timeline/cache"
@@ -144,6 +144,35 @@ test("disposes views on workspace changes while the destination is not rendered"
   expect(input.disposed).toEqual(["ses_a", "ses_a"])
 })
 
+for (const order of ["session-first", "workspace-first"] as const) {
+  test(`keeps views live across five workspaces when updates are ${order}`, () => {
+    const input = setup()
+    const render = createRoot((dispose) => ({ selected: createMemo(input.cache), dispose }))
+    const visited = ["ses_a"]
+    try {
+      ;["ses_b", "ses_c", "ses_d", "ses_e", "ses_a", "ses_c", "ses_b", "ses_e", "ses_d", "ses_a"].forEach(
+        (id, index) => {
+          batch(() => {
+            if (order === "workspace-first") input.setState("directory", `/repo/${id}`)
+            input.setState("id", id)
+            if (order === "session-first") input.setState("directory", `/repo/${id}`)
+          })
+          expect(input.disposed).toEqual(visited)
+          input.setState("messages", id, [
+            { id: `msg_live_${index}`, type: "user", text: "Live update", time: { created: index + 3 } },
+          ])
+          expect((render.selected() as HTMLDivElement).dataset.messages).toBe(`msg_live_${index}`)
+          expect(input.views.get(id)!.active()).toBe(true)
+          visited.push(id)
+        },
+      )
+    } finally {
+      render.dispose()
+      input.dispose()
+    }
+  })
+}
+
 test("evicts the least recently selected view and disposes all retained owners", () => {
   const input = setup()
   try {