I recently realized that unlike Chrome, Firefox does not ask for the computer's pin after copying a password saved within the browser's password manager. I find that this would be rather insecure if, say the computer was stolen and the would be thief logged into the computer and the proceeded to access all of your accounts due to the fact that all of the passwords are able to copied easily. Now, this problem can easily be mitigated if one uses 2FA, but if they have your computer, they probably have access to your email due to autofill. So I think requiring a password/pin or the computer password to copy a password would be great. Also, Firefox should remember when a password has been copied and in that instance/window, allow a user to copy passwords freely until the window is closed, just like Chrome.