[jools5000]

 I'm having the same issue. My TV is 4K but doesn't support HDR. Anything I play with HDR is too bright and washed out.   

Do you want to know an ever weirder thing.... i do have a 4k tv with HDR as my main computer screen, so i installed kodi 18 on that one and hocus pocus 4k movies are running just fine. So i don't think it's a bug in the new update. 

Just curious what OS are you running? my HTPC is running Win 10 Enterprise and my main computer is running Win 7 so it can be a bug with Win 10.   

I'm running Win 10 Enterprise LTSC. Kodi 17 played HDR movies for me just fine.  

It plays them, yes  However has no tone mapping to convert HDR to SDR and doesn't support HDR passthrough (result is everything looks awful)

If you're using DSPlayer edition or external players then the above doesn't necessarily apply

LTSC probably a bad idea, as we're waiting for MS to finally implement a HDR switching API, which LTSC wont necessarily get (especialy if they introduce it in the nect couple of years)