ZDoom

Could be, considering I can't find any actual documentation about the feature being disabled.

That sounds like another Monkeysoft bug.

No, unfortunately I don't have a link. All I can tell you is I installed the service pack, and hardware gamma no longer works. It doesn't work with Quake 3, and it no longer works with the actual gamma utility I used to use. (Which is a pain at night because I used to use it to darken my screen so that black-on-white text doesn't blind me)

Thank god that on my monitor I do not need it. That's not nice, though, how are those old closed source OpenGL games supposed to handle this then? They all depend on this feature.

Do you have a link?

Turns out we were two steps ahead of Microsoft on this one.

The latest Windows 10 service pack likewise removes support for hardware gamma completely, as well. Games that depend on it no longer look correct.

Since hardware gamma has been removed completely I don't think this is any longer relevant.

I'm not using hardware gamma, so when I launch gzdoom everything is fine. But when I close it, brightness jumps up, just like it happens on launch when hardware gamma is used. And it stays that way, which is supremely annoying. It happens with any verison, it seems; I tried 3.6 as well as a few latest dev builds.