Interestingly, the pop-up thumbnails one gets when hovering over the timeline as not affected; they look fine.
   One post by someone else was answered that it was a GPU driver issue; another said it's only with HD videos.
   I'm a B&W photographer and would really like to get back to normal again. 
   Any ideas?

Last week, mid-day one day, videos on YouTube suddenly all had a warm cast --yellowish for color, cream/beige for B&W. I have researched the issue as I can. It is not my Windows night light; my drivers and PC are apparently all updated; everything is working fine. I checked to see if the same happened with Vimeo videos and it did. I'm running W10. Interestingly, the pop-up thumbnails one gets when hovering over the timeline as not affected; they look fine. One post by someone else was answered that it was a GPU driver issue; another said it's only with HD videos. I'm a B&W photographer and would really like to get back to normal again. Any ideas?