I've activated ssh-agent service on my Windows 10 machine and set it to start automatically at boot. Next, I've added my ssh keys to agent using ssh-add and during this process ssh-agent asked for password to my keys. After that everything works as expected - I can log to my servers using ssh keys without entering password.
I've shut down my PC and next day after starting Windows Terminal I was able to log to my server without providing password to keys to ssh-agent which I find strange, because on Linux I have to add keys and provide password after every reboot.
I've checked Windows credential manager (in control panel), but nothing there seems to match.
What is happening here?