Xbox keeps disconnecting from tv when opening hdr games?

How are you viewing the screenshots, on your TV? When you play a HDR game, your TV automatically switches to HDR mode, and when you quit from the game, your TV exits from HDR mode. I think when you view an image your TV is still in non HDR mode.

May be you can try downloading the screenshot from OneDrive to your PC with a good screen and check if it looks good?

I have this problem on my Samsung 65" KS9000. I will get a message from the TV that HDR content is playing and then the video goes dull/washed out. The TV video settings themselves haven't changed. If I view the TV menu or open an app on the TV, color
is normal. When I minimize GOW4 or Netflix, the Xbox dashboard is dull and washed out. If I open a non HDR Xbox app like Youtube, colors will go back to normal. Go back into Gears of War 4, Netflix or the Bluray player, video goes bad. Even adjusting in
game brightness/HDR and the TV settings will not help because the color is so bad.

Same issue for me

Open Netflix and HDR enables on my TV even though I haven't started any HDR content. Stays in HDR mode until I open another app or game.

TV: Samsung JS8000

Hi Gilbot81 yes it’s amazing, I used fallout 4 to played on regular tv before I buy 4K HDR TV and when I brought the Samsung 4K HDR TV It’s was way different with the graphic and stunning game played on Fallout 4 on your Xbox One. It’s worth it and you
will love it. Holidays are around the corner and keep your eyes on sales of tv.

Yep. The TV goes into HDR mode when you open Netflix before you start viewing any HDR content. Then it screws up the colors for everything else on the Xbox until you hard reset, or change your output or TV settings. There's another, longer thread about it.