LyX ⇒ output fails with biblatex-3.12 and latin language

[ExecutorElassus]

I'm using lyx-3.3.99dev, using biblatex-chicago with biber, polyglossia, and xetex.

biblatex recently updated to version 3.12. After the update, I am no longer able to compile documents with the Latin language defined in the preamble (even though I have the texlive-langeuropean package installed). Previously this only threw a warning that it couldn't find the latin.lbx file and was falling back to another language, but now xetex compilation fails.

When I block the 3.12 version and downgrade to biblatex-3.7/biber-2.7, compilation runs successfully despite the warnings.

Is this a problem with Lyx, or with the biblatex/biber packages?

Thanks for the help.

EE

[Johannes_B]

Can you make a LyX document as small as possible and then export it to latex/xelatex?

Also posted on the biblatex issue page -> https://github.com/plk/biblatex/issues/872