This is extracted from this comment:
https://codereview.chromium.org/2537373005/#msg19

It seems than the fact that colors have the unvisited vs visited
values causes that we need to modify InterpolationType design.

On that CL we're making caret-color animatable,
however "auto" is still interpolable in some animations.
For example if you've:
  @keyframes caret-color-to-lime {
    to { caret-color: lime; }
  }
It sill interpolates the caret-color value, when it shouldn't.

But if you've:
  @keyframes caret-color-to-lime {
    from { caret-color: auto; }
    to   { caret-color: lime; }
  }
Then it doesn't interpolate, as expected.

Created new test "caret-color-021.html" (attached)
to reproduce the issue, and send it upstream:
https://github.com/w3c/csswg-test/pull/1163

 

Deleted: caret-color-021.html 1.1 KB

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