Hi,
How about ending and restarting the explorer.exe process? Does this issue occur with other user accounts? You can log on another user profile and launch the game to see if the issue occurs. If the issue persists, please use Registry Editor to delete the following registry key:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\StuckRects
When you restart Windows, the taskbar is automatically recreated.
Disclaimer: it is recommended to back up your registry before modifying. Any incorrect modification may cause unrecoverable damage.
Best Regards
Dale