On the lack of a SQUARE TB glyph

[Fred Brennan via Unicode]

Greetings,

I can't help but notice that there is no "SQUARE TB" glyph.

We have SQUARE KB, GB and MB, starting at U+3385. But no SQUARE TB?

SQUARE GB is at U+3387, and U+3388 is...SQUARE CAL, ㎈, so no space was even 
left for it—not very future-proof!

The purposes of these glyphs is, as you know, for CJK. Perhaps terabytes were 
not as common when these glyphs were approved, but they are common now.

There is a clear demand for a SQUARE TB. In the font SMotoya Sinkai W55 W3,  
which is ©2008 株式会社 モトヤ, the glyph is unencoded and accessed via the 
Discretionary Ligatures (`dlig`) OpenType feature. It has name `T_B.dlig`. 
This same scheme is used in many other Motoya fonts, and presumably other CJK 
fonts. In some other fonts, the `hwid` feature can be used to get a similar 
effect.

SQUARE TB is likewise seen often on packaging as terabyte hard drives are now 
common, as is the concept of a terabyte in operating systems.

Recently new glyphs were added for the new era name, so I don't think it's a 
problem to add SQUARE TB. While we're at it, may as well add SQUARE PB. To be 
future-proof (hopefully for the next hundred years!), perhaps we ought to also 
add SQUARE EB, SQUARE ZB and SQUARE YB! But even if only SQUARE TB gets in 
it's worth it, I need it.

Best,
Fred Brennan