Bug: Chromium unlock issue

I am using Bitwarden in my Edge Chromium. I set vault lock to after system restart and enabled PIN but it is locking itself after browser restart, not system restart.

How can I prevent it?

I can keep the vault unlocked indefinitely but I can’t make it keep unlocked itself after a browser restart.

Closing the browser removes the reference to your master key in memory, which will require you to unlock the vault again.

Another thread on this topic for reference:

So, what is the difference between on browser start and on system lock? Both have same result.