I'm a bit confused on when the URL checking is applied. Is the browser going to maintain a list of "good" domains and validate against that? If so then that'll

I'm a bit confused on when the URL checking is applied. Is the browser going to maintain a list of "good" domains and validate against that? If so then that'll need a lot of maintenance. Getting yourself on that list would need to go through some process that probably isn't transparent. If your legitimate website is too similar to one on the known "good" list, then it'll also probably be a process to get that resolved too all while you're losing visitors. If you attempt to automate this then there's a new risk that someone gets a malicious site in.