Controlling the password visibility
You can control the password visibility within the 1Password application. If you want them always shown you can choose the View > Conceal Passwords menu choice and make sure the check-mark is not shown beside the item. The default is to conceal passwords because the risk of exposing your passwords is high if a passerby “looks over your shoulder”.
If the Conceal Passwords menu choice is set, you can view the password(s) of the currently selected item by pressing down the Option (⌥) key on your keyboard. When you release the Option key the password(s) will be hidden from view again. You do not have to position the mouse to any particular location to use the Option key in this manner.
This capability does not exist on an actual web page where you (or 1Password) have filled in a password. Web form fields indicated as containing passwords are concealed automatically by your browser.