It does show HDR.
I flashed the file through the /storage/.update/ folder, enabled debug, rebooted and started the movie. Here the log:
Thanks for the log, dynamic range infoframe seems to be sent fine, not quite sure what might be going wrong.
Can you test with some publicly available samples, eg the ones from 4kmedia.org (4k HEVC 24fps ones should work well), and/or upload a short 20-30secs sample? Then we can try to reproduce it and have a closer look.
so long,
Hias