Respect explicit server placement for owner-pinned remote browser links (#17361)

When a remote browser pane opens a link with an explicit placementPreference,
honor that override rather than applying the generic browser client policy.
Links opened from remote panes may require specific host placement to respect
execution boundaries.

src/renderer/src/components/browser-pane/assemble-chrome/BrowserPane.remote-link-routing.test.ts

@@ -15,5 +15,6 @@ describe('remote browser link routing', () => {
 
     expect(openRequest).toContain('workspaceId: worktreeId')
     expect(openRequest).toContain('expectedRuntimeEnvironmentId: runtimeEnvironmentId')
+    expect(openRequest).toContain("placementPreference: 'server'")
   })
 })

src/renderer/src/components/browser-pane/stream-remote/remote-browser-page-pane.tsx

@@ -359,7 +359,8 @@ export function RemoteBrowserPagePane({
               workspaceId: worktreeId,
               url: linkUrl,
               intent: { kind: 'url' },
-              expectedRuntimeEnvironmentId: runtimeEnvironmentId
+              expectedRuntimeEnvironmentId: runtimeEnvironmentId,
+              placementPreference: 'server'
             }).catch((error) => {
               setPaneNotice({
                 kind: 'direct',

src/renderer/src/lib/workspace-browser-tab-open.test.ts

@@ -6,6 +6,7 @@ import {
 } from '../../../shared/execution-host'
 import { FLOATING_TERMINAL_WORKTREE_ID } from '../../../shared/constants'
 import { BROWSER_SCREENCAST_RUNTIME_CAPABILITY } from '../../../shared/protocol-version'
+import * as clientCreationActionPolicy from './client-creation-action-policy'
 import {
   canOpenWorkspaceBrowserTabOnRuntime,
   canOpenWorkspaceBrowserTabOnSsh,
@@ -241,6 +242,65 @@ describe('openWorkspaceBrowserTab', () => {
     expect(createBrowserTab).not.toHaveBeenCalled()
   })
 
+  it('keeps an asserted runtime link on its owner when policy selects the local client', async () => {
+    const createBrowserTab = vi.fn()
+    mocks.state = {
+      ...ownerState(toRuntimeExecutionHostId('hub-a')),
+      ...browserCapableRuntime('hub-a'),
+      createBrowserTab,
+      defaultBrowserSessionProfileId: 'client-profile',
+      defaultBrowserSessionProfileIdByHostId: {}
+    }
+    const policySpy = vi
+      .spyOn(clientCreationActionPolicy, 'getClientCreationActionPolicy')
+      .mockReturnValue({
+        'managed-browser': { state: 'enabled', provider: 'local-client' },
+        'mobile-emulator': { state: 'enabled', provider: 'local-client' }
+      })
+
+    try {
+      await openWorkspaceBrowserTab({
+        workspaceId: WORKSPACE_ID,
+        url: 'https://example.com/pinned',
+        intent: { kind: 'url' },
+        expectedRuntimeEnvironmentId: 'hub-a'
+      })
+
+      expect(mocks.createRemote).toHaveBeenCalledWith(
+        expect.objectContaining({
+          environmentId: 'hub-a',
+          waitForRegistration: true,
+          worktreeId: WORKSPACE_ID
+        })
+      )
+      expect(createBrowserTab).not.toHaveBeenCalled()
+    } finally {
+      policySpy.mockRestore()
+    }
+  })
+
+  it('forwards an explicit server placement for owner-pinned remote panes', async () => {
+    mocks.state = {
+      ...ownerState(toRuntimeExecutionHostId('hub-a')),
+      ...browserCapableRuntime('hub-a'),
+      createBrowserTab: vi.fn(),
+      defaultBrowserSessionProfileId: 'client-profile',
+      defaultBrowserSessionProfileIdByHostId: {}
+    }
+
+    await openWorkspaceBrowserTab({
+      workspaceId: WORKSPACE_ID,
+      url: 'https://example.com/pinned',
+      intent: { kind: 'url' },
+      expectedRuntimeEnvironmentId: 'hub-a',
+      placementPreference: 'server'
+    })
+
+    expect(mocks.createRemote).toHaveBeenCalledWith(
+      expect.objectContaining({ placementPreference: 'server' })
+    )
+  })
+
   it('fails closed when the workspace route swaps away from the pane runtime before opening', async () => {
     mocks.state = {
       ...ownerState(toRuntimeExecutionHostId('hub-a')),

src/renderer/src/lib/workspace-browser-tab-open.ts

@@ -8,6 +8,7 @@ import {
   type ExecutionHostId
 } from '../../../shared/execution-host'
 import { SEARCH_ENGINE_LABELS, type SearchEngine } from '../../../shared/browser-url'
+import type { BrowserClientHostPlacementPreference } from '../../../shared/browser-client-host-placement'
 import { FLOATING_TERMINAL_WORKTREE_ID } from '../../../shared/constants'
 import { BROWSER_SCREENCAST_RUNTIME_CAPABILITY } from '../../../shared/protocol-version'
 import {
@@ -31,6 +32,8 @@ export type OpenWorkspaceBrowserTabRequest = {
   selectWorktree?: boolean
   expectedRuntimeEnvironmentId?: string
   expectedSshConnectionId?: string
+  /** Override placement for links whose pane explicitly requires server ownership. */
+  placementPreference?: BrowserClientHostPlacementPreference
 }
 
 function isExpectedRuntimeBrowserRoute(
@@ -272,7 +275,9 @@ export async function openWorkspaceBrowserTab(
       `host ${route.executionHostId} does not own runtime ${environmentId}`
     )
   }
-  if (availability.provider === 'local-client') {
+  // An asserted runtime owns links opened from remote panes; provider policy may describe the
+  // viewing client's generic browser surface rather than that pane's execution host.
+  if (expectedEnvironmentId === null && availability.provider === 'local-client') {
     const localHostId = host && host.kind !== 'runtime' ? host.id : LOCAL_EXECUTION_HOST_ID
     createClientBrowserTab(state, request, localHostId, presentation)
     return
@@ -286,6 +291,9 @@ export async function openWorkspaceBrowserTab(
       targetGroupId: request.targetGroupId,
       // Owner-pinned links need the host tab published before client reconciliation.
       ...(expectedEnvironmentId !== null ? { waitForRegistration: true } : {}),
+      ...(request.placementPreference !== undefined
+        ? { placementPreference: request.placementPreference }
+        : {}),
       // Why: the tab is opened from this workspace's tab bar, so surface that
       // workspace — otherwise a background worktree looks like nothing happened.
       ...(request.focusOnCreate !== undefined ? { focusOnCreate: request.focusOnCreate } : {}),