I wouldn’t say that it’d be strictly impossible, however if it can be done then it would come at a considerable cost to useability, versatility, etc.

One adjacent concept that comes to mind is the use of the :visited CSS tag to extract a user’s browsing habits. I remember seeing a demonstration of this where an “are you human” captcha was shown but the choice of image in each box was controlled by the :visited tag. I can’t find that post, but this medium article demonstrates a similer concept. There are mitigations to this luckily, but a fullproof solution would be to remove the tag’s functionality altogether, which would make certain websites (like the one we’re on right now!) much more inconvenient to use.

It seems trivial to me for a website to detect user behaviors that indicate the use of an adblocker. For example, if a request for a page is immediately followed by a request for a video on that page, rather than after 5-60 seconds, then they’re likey using an adblocker. If there is an ad placed between two paragaphs in an article, but two distant paragraphs are visible at the same time, it is more likely (although not guaranteed) that they are using an adblocker. If a user triggers an abnormal amount of those heuristics then they get flagged as an adblocking user.

Uganda ain’t blue enough!

I honestly assumed I was colorblind in one eye (I am diagnosed, at least)

I dunno, having two primes sum to a power of two is undeniably powerful in my experience. The number of times a calculation goes from tedious to trivial from this sum is incalculable. The lowest I’d put it is A.

Huh. When I took Calculus II in community college, the professor introduced sum notation and like 2/3 of the class was like “wow that’s cool I didn’t know about that”. I don’t remember ever being formally taught it before that but it still surprises be how few people where already familiar with it.