ZWJ, ZWNJ and Markup languages.

[Plug Gulp]

Hi,

The Unicode standard 8.0 states in chapter 23, section titled "Cursive
Connection and Ligatures"(printed page #814, PDF page #850) that:

"The zero width joiner and non-joiner characters are designed for use
in plain text; they should not be used where higher-level ligation and
cursive control is available. (See Uni-code Technical Report #20,
“Unicode in XML and Other Markup Languages,” for more information.) "

I went through TR#20 and did not find any mention that ZWJ and ZWNJ
are not suitable for use with markup languages. On the contrary, ZWJ
and ZWNJ are listed in TR#20 under section 4 titled "Format Characters
Suitable for Use with Markup".

So are ZWJ and ZWNJ characters suitable for use with markup languages
such as HTML and XML?

Thanks and kind regards,

~Plug