[tex-k] bibtexu crash

[Hironobu Yamashita]

Hi Karl,

> Yes, I get the same failure with tl21 bibtexu and ICU. Apparently
> something in ICU has new requirements or backward incompatibilities.

How unfortunate ...
When I tested in 2019, I found that bibtexu worked on some platform and
doesn't on others. I guess making it ok everywhere would require much work,
and I don't have enough knowledge about icu.

Hironobu