This is a browser feature, rather than something specific to the VM website - you should be able to find in your browser settings where passwords are cached (in chrome it’s Profile -> passwords (both pictures - the “profile” button is the circle next to the three dots in hte top right corner, and the passwords is the small key that appears when you click the profile button). You can manage which sites you store/save passwords for there.
Alternatively, you can just type chrome://settings/passwords into the address bar and hit enter.
Other browsers i’m not familiar with but if you have a root around the settings menu you’ll find it.