Privacy Badger gave me one hit, netdna-ssl, at the "Blocked Cookies" level. No hits on uBlock or the new enhanced tracking protection thing. What trackers are you seeing?
"You can also now do crazy stuff like having multiple mice with multiple cursors, and linking keyboards, mice, drawing tablets, and touchscreens to each other arbitrarily. You can now have your dvorak keyboard for normal use and a second qwerty keyboard for when your coworker comes over for a pair programming session. You can even give your coworker the ability to focus and type into separate windows from what you’re working on."
I'm certain multiple mice is (or at least, was) supported on Windows, i remember some of Reflexive Entertainment's games from around mid-2000s having what they called "Mouse Party" which was basically a local multiplayer mode with multiple mice connected to the same PC (their games were casual indie games with simple control schemes that often supported something like that).
In theory multiple mice and keyboards are possible on X too since late 80s/90s, at least assuming the XInput extension is available on the server since the core events do not provide any way to differentiate between devices. But like everything with X, the feature might be there, but it is up to the clients to actually use it and use it properly (which isn't always the case and a lot of "X cannot do <thing>" you hear really means "due to the way we use X, we cannot do <thing>"). And even if the feature is there, if it is a niche case, it may be so buggy that it isn't practically usable (of course this applies to almost every open source project that is older than a couple of years, especially those that are big and have a small number of contributors).
An example of this would be multiple focused windows (one per keyboard) - despite XInput allowing for such a thing, i doubt many window managers and toolkits would be able to handle it (and to be frank, neither does my own toolkit and most likely will never have support for it - it is so niche of a feature, it isn't worth the time and increase in complexity and potential future maintenance).
"You can now have your dvorak keyboard for normal use and a second qwerty keyboard for when your coworker comes over for a pair programming session"
Well over a decade ago, I had multiple keyboards with different layouts hooked up to my linux laptop, and could use both of them at the same time with no problem.
Mainly that a spreadsheet program is available on most laptop/PCs. And most people have been taught how to use an 'office' package at some point. And the UI is sort of built in and familiar.
Perhaps you will be able to sleep easier when the Raspberry Pi' generation come of age? I recollect that small business people built applications with Hypercard a few decades ago.
They do allow people to walk up and start building models with minimal introduction. Low floor, and, alas, as many know here to their cost, a high ceiling in the sense that spreadsheets often get used for more advanced modelling that would benefit from being constructed in a more maintainable way.
Fragments of a Hologram Rose (1977) also by Gibson already had this.
Does anybody know even earlier instances?