The best way to open the Startup folder in Windows 10 is with the address shell:startup, you can enter this path in address bar of MS Explorer.

Or use the Run-Dialog Box [Windows-logo] + [R] in Windows-10 and enter the command shell:startup
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The second startup folder in Windows 10 shell:common startup is responsible for all users, when here, an entry is created, or deleted, this is valid for all users on the Windows-10 PC. (… see Image-2 Arrow-1)

Here is the alternative addresses, this can you use to create a new Windows 10 desktop shortcut.

Autostart for currently logged-on user:
shell:startup = %appdata%\Roaming\Microsoft\Windows\Start Menu\Programs\Startup

And startup folder all users:
shell:common startup = %programdata%\Microsoft\Windows\Start Menu\Programs\Startup

Tip
shell:start menu = start menu in Windows-10
shell:common start menu = all user start menu in Windows-10