HLG definitely doesn’t work as well under OSMC as it has done in earlier releases. In particular, the “football” HLG test loop on iPlayer doesn’t play correctly - but it used to, and it does play correctly on other devices. Something got broken in the August build, I think, or shortly before that.
and [TESTING] Kodi v19 builds for Vero 4K / 4K + - #864 by dajoe