Obviously using Brave as per the private tab color, but it's very unlikely to be Brave-specific.
Fortunately, switching between light and dark mode in the browser settings immediately reflects for me, but it makes the specs a lot harder to read ordinarily and is probably a CSS oversight. Also, this isn't specific to that spec, just that's one spec where I have those issues.
Example: https://drafts.fxtf.org/filter-effects/#element-attrdef-fecolormatrix-values
Dark mode:
Light mode:
Obviously using Brave as per the private tab color, but it's very unlikely to be Brave-specific.
Fortunately, switching between light and dark mode in the browser settings immediately reflects for me, but it makes the specs a lot harder to read ordinarily and is probably a CSS oversight. Also, this isn't specific to that spec, just that's one spec where I have those issues.