There are all sorts of tricks. Doesn't matter how much you warn the sheep about wolves, they'll do what they want. That's what sheepdogs are for ...
When I was running sites on dial-up, before Al Gore invented the internet, I'd pre-load the 'next page' on the 'previous page' by making the 'next page' 1 x 1 px. and put it at the bottom of the 'previous' page.
Users never saw the 1 x 1 px. page at the bottom of the normal size previous page. All they had to do is look at the source code. Hello ?!?!?
How many sheep are going to do that? They just marveled at how fast my sites were. They didn't realize that the next page was being quietly buffered to their cache in the background in advance.
Mind you, this wasn't malicious in any form or fashion, just sneaky. But, it's all too easy to turn good intentions into mischief, when you're dealing with unsuspecting fools.
Best way to protect yourself is to
setup a honeypot on your machine and troll the perps, like you do with web servers. It's great sport, but I digress ...
BTW, for shiggles I hid a 480 x 360 px. pic, with a solid black background, in this post. Can you find it ?
It's NOT a malicious act, but could just as easily have been child porn and got you arrested and/or fired from your job, et cetera.
Just saying

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