bug#39390: 28.0.50; prettify-symbols-mode confuses display when start/end faces are different

[Raphael 'kena' Poss]

On 17-02-2020 12:30, Eli Zaretskii wrote:
> So this limitation is not
> really arbitrary, and can only be lifted by a thorough redesign of how
> the display engine traverses the text it is about to display, and what
> it does when it meets a composition that crosses face boundaries.

My humble opinion on this is that either the compose function should
report an exception / error, or pick some arbitrary behavior (e.g. just
use the 1st face for the entire substitution) and use that.

It seems strange to me to accept the current non-deterministic,
display-corrupting behavior as a reasonable alternative.

-- 
Raphael 'kena' Poss