Hello,
Thank you for posting in Q&A forum.
I'm sorry this may be by design, there is no relevant group policy or registry to modify this setting.
However, through my search, refer to the following discussion link: How do I stop the Windows 10 start menu from opening upon login to Windows? - Super User
Create a Windows Hibernate Keyboard Shortcut or Desktop / Taskbar Icon (trickyways.com)
You may try to set a hotkey combination to achieve that the "Start" menu will not appear after unlocking the computer.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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