When using browser plugins, I wonder if I can fill passwords without entering the master password; and only need to enter the master password when I want to view passwords and other hidden fields. And I want to apply this method to all my projects.
What settings are you using for your vault timeout period and vault timeout action?
You can configure your vault so that it locks instead of logging out, and you can control how frequently it locks, and what method you will use for unlocking (e.g., biometrics or a PIN). This way, you can reduce or eliminate the need for entering your master password when autofilling passwords.
Another option that you may find useful is the Master Password Reprompt, which will require the master password to be entered to view any hidden fields for the items that have this extra protection enabled. However, enabling Master Password Reprompt on an item will also require the master password to be entered when autofilling (otherwise, someone with access to your unlocked vault could just autofill the password into the login form, and toggle the password visibility on the form itself to see the password).