If websites are able to track their users’ typing behavior and mouse movements, then the websites may be able to use that data to fingerprint, track, and possibly identify their users. Is this a real privacy risk? If so, what are the methods to counter keyboard and mouse fingerprinting by websites? Note that I do not want to disable JavaScript.
There are much easier things to fingerprint than user mouse and keyboard behavior. Your browser gives a lot of meta and capability information to the website.
To fingerprint, identify, and distinguish users and people through behavior you’d have to take a probabilistic approach and track enough data long enough.
If you’re still concerned and want to prevent it, you’d have to prevent the website from receiving mouse and keyboard events. Use an adjusted browser that would disable or use a browser that can do so through an extension with an extension, to prevent javascript addEventHandler and other interactive elements from receiving interactivity events. Note that this may go as far as having to disable hovering highlights if you want to be thorough.
I wouldn’t be too concerned about behavior analysis identification - at least not generally.