Proposal for BiDi in terminal emulators

[Eli Zaretskii via Unicode]

> From: Egmont Koblinger <egmont at gmail.com>
> Date: Fri, 1 Feb 2019 14:16:03 +0100
> Cc: Adam Borowski <kilobyte at angband.pl>, unicode at unicode.org
> 
> There's absolutely no way we could reorder first, and then handle
> TAB's cursor movement. TAB's cursor movement happens in the lower
> layer, reordering happens in the upper one.

But that means you won't ever be able to be in compliance with UAX#9,
because TAB has distinct properties that affect the UBA.  If you
reorder after all TABs have been converted to spaces, you will not be
able to implement the support for Segment Separator characters.  Am I
missing something?