Andreas SchneiderAre you a Linux Gamer? Do you have a HDR screen but run it in Eco (sRGB) mode for your daily work? Do you want to turn HDR on for games (or other stuff)?
I have the solution for you (for KDE Plasma):
Original idea by Mika Norén from https://discuss.kde.org/t/toggle-screen-hdr-on-or-off-automatically-with-this-script/29253
Toggle screen HDR on or off automatically with this script
Got a fancy nice HDR monitor? Love that KDE plasma desktop helps utilise HDR? Tired of manually toggling HDR on or off depending on what you’re doing? Can’t stand editing a bunch of custom launch options or PRE/POST scripts for each game/application each time the screen setup changes? (i.e. laptop docking stations or KVM switches) And yeah… having your ICC profile erased each time an HDR title is launched is another annoyance we solve here. (Optional) … Fret no more. Here’s a lil helper-sc...
Aris Adamantiadis 
💲Paid@cryptomilk interesting! I don't even know how to turn HDR on gnome/X11