Even basic things like auto-suggestions in the URL bar can't be turned off any more. A while ago there used to be an option for it but it was removed. So when you enter an URL it's automatically sent to Google as you type.
At some point the new tab page stopped being replaceable something less distracting/compulsive like your own custom url. Your homepage can only apply at startup. It isn't something that should have to be an extension.
