Windows 11 multi-monitor: after disconnecting external display, taskbar only shows apps from that display; other open windows missing

Environment: Windows 11 25H2 (OS Build 26200.9711), ThinkPad T14 Gen6. External monitor Dell P2723DE connected via USB-C. Two virtual desktops in use. Taskbar setting “Show my taskbar apps on: taskbar where window is open”.

Steps to reproduce:

Connect the external monitor (extended mode). Windows are spread across both displays; each taskbar shows its own apps.

Disconnect the external monitor.

All windows move to the laptop screen (Task View shows them all).

Expected: The laptop taskbar shows buttons for all open windows.

Actual: The laptop taskbar only shows the apps that were on the external monitor’s taskbar (Firefox, File Explorer, Word, a browser). Apps that were on the laptop the whole time (Teams, Outlook, PowerPoint, Settings, Phone Link) have no taskbar button, though they are running and reachable via Alt+Tab/Task View.

Frequency: every time

Tried: restarting Explorer fixes it until next external monitor reconnection

Screenshots: attached, taken before and after disconnecting.

before disconnecting:

after disconnecting: