And again, this doesn’t prevent redistribution.
Also I assume it's working in a the way intended. It may be a stupid thing to do from your or my perspective because it doesn't work towards our benefit – but the rational behind it is sane. That's what I meant with „not stupid”.
I just realize I sound like this sickening utilitarian tone you find in HN discussions so often. Sorry for going that way. Basically I'm with you, it's stupid when you take a step back.
My point is that a prevention mechanism can have utility for those employing it, even if it’s trivially circumvented by those who really want to. It does not have to be a binary thing, where either it works perfectly 100% of the time or it’s useless. It’s obvious to me that this feature could have a stifling effect on spread of content, and that might be well enough to have fulfilled its purpose.
Mind you, ideologically I do not necessarily agree with it, but that’s another matter.
How do they enforce it on the web client?