Is the Mouse a Full Proxy for Eye Tracking?

The mouse approach can be a full proxy if eye tracking was too expensive or just not available for my project, but I do have mouse data. Can I get just the same rich amount of information as dataset, or is there like a fidelity loss by looking at only the mouse? Yeah, well, it depends on the task. But with the mouse, we can do very large-scale studies. We don't need the eye tracker anymore, in a sense. Especially if we know that the page that we are going to investigate ... It's something that we believe is worth of exploration by using the mouse instead of the eye, of course.