[swid]

The suggestion in that post about how to fix it is good, and mirrors one I read in the Rachael by the Bay blog - type the number of machines to continue:

https://rachelbythebay.com/w/2020/10/26/num/

The take away by both is there is actually something to do which can wake people up when the stakes are high, and they might not be doing what they expect.

[oauea]

And most importantly, don't let yourself get into the habit of copy pasting the value

[underwater]

I wonder if your could print some non visible characters in there to taint the copied value in some detectable way.

[dkersten]

Prompt in words, but expect the value in numbers, eg: "Twenty-five" and the box requires you to type "25"? At least this specific case, it would require you to type it.

[weaksauce]

yeah, that would possibly stop the copy and paste problem. to make it robust they would need to use a string of a few non-visible characters but that would fail if the browser's clipboard system doesn't copy them over for some kind of privacy initiative. might be another way it fails that I can't think of right now.