Created attachment 358053 [details]
Steps to reproduce the problem:
Open this file.
What is the expected behavior?
The underline should be green rather than yellow as the same color of the text.
What went wrong?
The underline is also yellow.
Firefox has the right behavior, but got a bug report for this behavior: https://bugzilla.mozilla.org/show_bug.cgi?id=1514467
Blink has the same behavior as WebKit.
It can be seen that the resolved value of text-decoration-color of the element returned from gCS is (correctly) green, however, it's ignored by rendering.
However, if I explicitly add text-decoration-color declaration to the style attribute, the resolve value keeps the same but the rendering is correct.
This behavior doesn't conform to the spec, and it doesn't make much sense to me.
We should fix this because we just unprefixed this property.