If a browser is hijacked, can the hijacker install keyloggers?

Or would they need more access than just hijacking the browser?

I've read that once i restart my desktop after closing the tabs where the hijacking took place that my browser is no longer being hijacked.

If they could install keyloggers while hijacking my browser, would the keyloggers also be gone after restarting the computer?

I have to admit i need to read more about keyloggers.