Thumbnail colour palette

Most channels that feel consistent are running three or four colours, usually a background, a highlight and a text colour, applied the same way every time. Recognition is the point. Someone scrolling fast should know whose video it is before reading the title.

Two things break it. Colours close to YouTube's own interface sink into the page, since the feed is white or near-black depending on the viewer's theme. And a palette enforced over the picture produces a wall of thumbnails nobody can tell apart.