Problem with russian text and opensans

[Putzar, Robin]

Hi,

I recently upgraded to TexLive 2024 and now have a problem compiling documents with Russian text with opensans. A minimum working example:

\documentclass{article}
\usepackage[russian,ngerman]{babel}
\usepackage{opensans}
\babelfont[russian]{rm}{opensans}
\begin{document}
Test \foreignlanguage{russian}{тест}
\end{document}

When compiling this with LuaLaTeX, I receive the following error in the line with \foreignlanguage:

Illegal parameter number in definition of \l__exp_internal_tl.

I remember that with TexLive 2023 there was no such error. I can ignore this, and the output looks fine. However, this is kind of annoying, and I'd like to know how to avoid this error. Any help is greatly appreciated. Thanks!

Best regards
Robin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 7965 bytes
Desc: not available
URL: <https://tug.org/pipermail/tex-live/attachments/20240430/3b6a7c87/attachment.p7s>