Most browsers still don't have a second line of defense (like password managers do), correct? So, if a user has access to my browser for two mins, they can see

Most browsers still don't have a second line of defense (like password managers do), correct? So, if a user has access to my browser for two mins, they can see all my passwords in plain text. They can't if my passwords are in password managers which will ask for my master password. I never understood why browsers didn't give an option to have a bit more security with those passwords. Just let the user enter one master password before they can see their stored passwords.