It's a very unusual "character" as it can sometimes be rendered very, very wide- the same width as maybe 20 or so "normal" characters. (whatever "normal" means. The more I learn about unicode...) The same width as if you had typed it out in a sentence.
It breaks a lot of UIs that use character count as a proxy for string width.
Given that writing systems we have today are pre-digital systems of marks made with the human body and tools, all encoding of text in our HCI is a simulation of writing. Simulations by nature cannot be 100% accurate. choices have to be made about what is represented and simulated. choices have to be made about what to leave out. Simulations are a form of communication, they put forward a perspective about what is the important part of what is being simulated.
Seeing a symbol like "﷽" really brought home for me some of the assumptions about writing that I take for granted, and are inherently "argued for" by the way text is handled in our digital systems.
I don’t think that’s right. I looked into the way Twitter counts characters when I was trying to work out the largest prime number that could be written out in full, in base ten, in a single tweet[1]; the rules are more complicated than you might expect, and have changed several times.
The current rule seems to be that all Unicode characters count as two, except for the ranges 0–4351, 8192–8205, 8208–8223 and 8242–8247 which count as one.
Good point! Still, I could swear I saw someone (@FakeUnicode?) do exactly this once, but of course I can’t find that tweet any more, partly because it turns out that search engines don’t handle ﷽ well at all, and I don’t feel like testing it on my own followers somehow.
Edit: it looks like it might count it as two characters, so that’s only 140 per tweet.
That’s definitely possible! @FakeUnicode mentioned in the discussion that, when 280-character tweets were first introduced in September 2017, it was possible to tweet 280 single-codepoint emoji using TweetDeck.
[1] https://github.com/minimaxir/big-list-of-naughty-strings/blo...