libjxl ABI seems to be C-only. However the whole library is written in c++ with
heavy use of libstdc++. libjxl is compiled with flags `-fno-exceptions` but is
linked againt the throwing libstdc++ from Debian.

This matter has been discussed with upstream, and it is not clear to the
package maintainer what is supposed to happen when libstdc++ is throwing an
exception, since it cannot propagate after the C-only ABI.

Ref:
* https://github.com/libjxl/libjxl/issues/904

 -- Mathieu Malaterre <malat@debian.org>  Tue, 14 Dec 2021 10:29:22 +0100