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chromium/third_party/blink/web_tests/fast/canvas/bug1281185.html 

<!DOCTYPE html>
<html>
<head>
<title>Regression test for crbug.com/1281185</title>
</head>
<body>
</body>
<script>

if (window.testRunner) {
    testRunner.waitUntilDone();
}
const w = 100;

const canvas1 = document.createElement('canvas');
canvas1.width = canvas1.height = w;
// Specifiy willReadyFrequently to ensure continued test coverage after
// GPU fallback heuristic changes.
const ctx1 = canvas1.getContext('2d', {willReadFrequently: true});

const canvas2 = document.createElement('canvas');
canvas2.width = canvas2.height = w;
const ctx2 = canvas2.getContext('2d');
document.body.appendChild(canvas2);

ctx1.fillStyle = '#f00';
ctx1.fillRect(0, 0, w, w);

// Triggers heuristic to fallback from GPU-acceleration
let data = ctx1.getImageData(0, 0, 1, 1);

// without this it behaves correctly (in chrome)
ctx2.drawImage(canvas1, 0, 0);

requestAnimationFrame(() => {
    ctx1.globalCompositeOperation = 'source-in';
    ctx1.fillStyle = "#0f0";
    ctx1.fillRect(0, 0, w, w);
    data = ctx1.getImageData(0, 0, w, w);
    ctx2.drawImage(canvas1, 0, 0);

    if (window.testRunner) {
        testRunner.notifyDone();
    }
});

</script>
</html>