<!doctype html> <html class="reftest-wait"> <head> <title>Bug 1216842: effect-level easing function produces negative values (main-thread)</title> </head> <body> <div id="target"></div> </body> <script> var target = document.getElementById("target"); var effect = new KeyframeEffect( target, { color: ["red", "blue"] }, { fill: "forwards", /* The function produces negative values in (0, 0.766312060) */ easing: "cubic-bezier(0,-0.5,1,-0.5)", duration: 100 } ); var animation = new Animation(effect, document.timeline); animation.pause(); animation.currentTime = 250; document.documentElement.className = ""; </script> </html>