Each pair below is the most saturated sRGB value on the left and the most saturated Display P3 value on the right, same channel pattern. If the two halves of a pair look identical, this browser is clipping P3 to sRGB and the brand-color preview cannot show the difference.
On the brand rows: if "P3 max" looks the same as "clipped to sRGB", the browser is clipping. On a true P3 output the middle swatch is visibly more saturated than the right one at about the same lightness.