Since todays update luatex on windows is back to 1.16: This is LuaHBTeX, Version 1.16.0 (TeX Live 2023) development id 7567 and similar for luatex. Since 1.17 was installed as a security fix I restored from the backup and there I have a development id 7581. -- Ulrike Fischer http://www.troubleshooting-tex.de/