Friends were talking about the new gradient added to the progress bar on Youtube videos.
I used inspect element to see if it could be disabled. Turns out you can just set it to whatever color you want.
You can use a CSS addon (i.e. User CSS for Chrome, CustomCSS Injector for Firefox) to make it permanent.
Not trans myself, but it's very nifty for pride colors :3
Just copy/paste this into a CSS addon and change the RGB hex codes to whatever color you want
ytp-cairo-refresh-signature-moments .ytp-play-progress
{background: linear-gradient(to right,
#5bcefa 0%,
#5bcefa 20%,
#f5a9b8 20.01%,
#f5a9b8 40%,
#ffffff 40.01%,
#ffffff 60%,
#f5a9b8 60.01%,
#f5a9b8 80%,
#5bcefa 80.01%,
#5bcefa 100%
);}