This is a testharness.js-based test.
Harness Error. harness_status.status = 1 , harness_status.message = 1 duplicate test name: "Uses of var() in CSS keyframes are responsive to changes in custom properties."
[PASS] Uses of var() in CSS keyframes are responsive to changes in custom properties.
[PASS] Uses of var() in CSS keyframes are responsive to changes in custom properties.
Harness: the test ran to completion.