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.

I have a “JavaScript off by default” approach and things generally work fine for me. I enable system functions on an as-needed basis; most sites don’t need to know what my mouse and keyboard are doing, so I don’t let them. In the rare case where it’s needed, I have it turned on for that particular location.

It takes a few weeks of frustration to set up, but I did this over a decade ago, and I’m down to maybe a site every 3 months or so where I need to tweak something. Usually when something doesn’t work right, I investigate and realize that I shouldn’t be visiting the site in question at all, and should find an alternative source.

There's a hidden option in Firefox's about:config if you Google fingerprint Firefox you'll find it.

I tried to turn it on but almost every site worked like it didn't save cookies and asked for captchas.

It became very annoying so I turned it off and just installed another browser for those kind of searches that you don't want to be tracked like Amazon... Totally not pron, I wouldn't do that.

I used to have a piece of software that had a phantoms mouse. You move this phantom pointer to where you want the mouse to be, and middle click (or something, it's been several years), and the real pointer would be moved there on a smooth line movement. It was used to allow an old piece of software to work with windows XP. Could be useful here.

For keyboard, just type in notepad++, then copy and paste into the text field.