Sadly, in attempting to fix it myself, I completely screwed my settings up, and ended up downloading old versions until I got things working back the way I wanted. (well, for the UI settings. Though it fixed the color problem, lul)
Well... kind of fixed. When the window is in motion the color issue happens, but once it stops, it goes back to normal.
EVGA graphics card... I'm pretty sure.
@burnout426 Only Opera GX was showing this issue. Chrome and Firefox continually displayed the proper color at all times, so wasn't a Windows setting, unless it was something specifically happening when OGX was not full screen. Even though it was, still... just rolled down one tick. shrug
Anyway, I can't test any solutions. I hope should anyone else encounter this issue (which searches showed it has popped up in the past), they can pick up the torch from here.
Thanks, friends :3