Forcing a Start menu layout without restarting Explorer

One user was trying to set the Windows 10 Start menu layout with Group Policy's Start Layout setting. They found that changes to the layout XML file only took effect after restarting Explorer or logging out then back in. For a while I thought it was impossible to make Explorer reload the XML (none of the usual Win32 change notification functions worked), but then I found that restarting just the Windows Shell Experience Host process (shellexperiencehost.exe) will do the job without interrupting other Explorer functions. It'll automatically come back right after being terminated.