a character for an unknown character

[Christoph Päper]

Marcel Schneider <charupdate at orange.fr>:
> On Sat, 31 Dec 2016 11:01:16 +0100, Christoph Päper wrote:
>> 
>> It has indeed. That’s why two different technologies have to be used to get 
>> typographically harmonic hexadecimal numbers, e.g. in CSS: …
> 
> Thank you for the code. I didnʼt know this,

Well, case-insensitivity was intended as *an* argument in favor of encoding digits A–F/a–f, although I know that there are also good arguments against it. (There are certainly also arguments in favor of encoding 0–9 another time just for hexadecimal numbers.)

> so Iʼve tried and found that 
> the automatic prefixes/suffixes cannot be copied from the web page. 

Browsers are still disagreeing about that, but yes, since the affix is generated content by CSS it is considered style and is likely to not get pasted into plain text environments. One could also argue that CSS should be able to render numbers in different styles and bases, but that’s currently neither supported nor planned.

> Among the possibilities, you include Unicode subscripts.

Just for the sake of completeness.

> The font-variant-numeric: oldstyle-nums seems not to work with any font. 

Browser and font support is required and limited, but not as much as few years ago.

> I note that the "U+" prefix is missing in the list, obviously because it 
> denotes more than just a hexadecimal number, and is to be hard-coded.

Yes, I was talking about hexadecimal numbers in general, not limit to Unicode code points.