Steps i tried to make program (for example: Thunderbird) to load on startup, but minimized:

1. Placed shortcut under: C:\Users\Username\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
2. In a shortcut properties i've checked "minimized"

Rebooted windows, it does start, but MAXIMIZED! Can't make it minimized, just like on MacOS i could set it hidden.