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diff --git a/testing/web-platform/tests/streams/transferable/reason.html b/testing/web-platform/tests/streams/transferable/reason.html
new file mode 100644
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+++ b/testing/web-platform/tests/streams/transferable/reason.html
@@ -0,0 +1,132 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/helpers.js"></script>
+<script>
+'use strict';
+
+// Chrome used to special-case the reason for cancel() and abort() in order to
+// handle exceptions correctly. This is no longer necessary. These tests are
+// retained to avoid regressions.
+
+async function getTransferredReason(originalReason) {
+  let resolvePromise;
+  const rv = new Promise(resolve => {
+    resolvePromise = resolve;
+  });
+  const rs = await createTransferredReadableStream({
+    cancel(reason) {
+      resolvePromise(reason);
+    }
+  });
+  await rs.cancel(originalReason);
+  return rv;
+}
+
+for (const value of ['hi', '\t\r\n', 7, 3.0, undefined, null, true, false,
+                    NaN, Infinity]) {
+  promise_test(async () => {
+    const reason = await getTransferredReason(value);
+    assert_equals(reason, value, 'reason should match');
+  }, `reason with a simple value of '${value}' should be preserved`);
+}
+
+for (const badType of [Symbol('hi'), _ => 'hi']) {
+  promise_test(async t => {
+    return promise_rejects_dom(t, 'DataCloneError',
+                               getTransferredReason(badType),
+                               'cancel() should reject');
+  }, `reason with a type of '${typeof badType}' should be rejected and ` +
+     `error the stream`);
+}
+
+promise_test(async () => {
+  const reasonAsJson =
+        `{"foo":[1,"col"],"bar":{"hoge":0.2,"baz":{},"shan":null}}`;
+  const reason = await getTransferredReason(JSON.parse(reasonAsJson));
+  assert_equals(JSON.stringify(reason), reasonAsJson,
+                'object should be preserved');
+}, 'objects that can be completely expressed in JSON should be preserved');
+
+promise_test(async () => {
+  const circularObject = {};
+  circularObject.self = circularObject;
+  const reason = await getTransferredReason(circularObject);
+  assert_true(reason instanceof Object, 'an Object should be output');
+  assert_equals(reason.self, reason,
+                'the object should have a circular reference');
+}, 'objects that cannot be expressed in JSON should also be preserved');
+
+promise_test(async () => {
+  const originalReason = new TypeError('hi');
+  const reason = await getTransferredReason(originalReason);
+  assert_true(reason instanceof TypeError,
+              'type should be preserved');
+  assert_equals(reason.message, originalReason.message,
+                'message should be preserved');
+}, 'the type and message of a TypeError should be preserved');
+
+promise_test(async () => {
+  const originalReason = new TypeError('hi');
+  originalReason.foo = 'bar';
+  const reason = await getTransferredReason(originalReason);
+  assert_false('foo' in reason,
+               'foo should not be preserved');
+}, 'other attributes of a TypeError should not be preserved');
+
+promise_test(async () => {
+  const originalReason = new TypeError();
+  originalReason.message = [1, 2, 3];
+  const reason = await getTransferredReason(originalReason);
+  assert_equals(reason.message, '1,2,3', 'message should be stringified');
+}, 'a TypeError message should be converted to a string');
+
+promise_test(async () => {
+  const originalReason = new TypeError();
+  Object.defineProperty(originalReason, 'message', {
+    get() { return 'words'; }
+  });
+  const reason = await getTransferredReason(originalReason);
+  assert_equals(reason.message, '', 'message should not be preserved');
+}, 'a TypeError message should not be preserved if it is a getter');
+
+promise_test(async () => {
+  const originalReason = new TypeError();
+  delete originalReason.message;
+  TypeError.prototype.message = 'inherited message';
+  const reason = await getTransferredReason(originalReason);
+  delete TypeError.prototype.message;
+  assert_equals(reason.message, '', 'message should not be preserved');
+}, 'a TypeError message should not be preserved if it is inherited');
+
+promise_test(async () => {
+  const originalReason = new DOMException('yes', 'AbortError');
+  const reason = await getTransferredReason(originalReason);
+  assert_true(reason instanceof DOMException,
+              'reason should be a DOMException');
+  assert_equals(reason.message, originalReason.message,
+                'the messages should match');
+  assert_equals(reason.name, originalReason.name,
+                'the names should match');
+}, 'DOMException errors should be preserved');
+
+for (const errorConstructor of [EvalError, RangeError,
+                                ReferenceError, SyntaxError, TypeError,
+                                URIError]) {
+  promise_test(async () => {
+    const originalReason = new errorConstructor('nope');
+    const reason = await getTransferredReason(originalReason);
+    assert_equals(typeof reason, 'object', 'reason should have type object');
+    assert_true(reason instanceof errorConstructor,
+                `reason should inherit ${errorConstructor.name}`);
+    assert_true(reason instanceof Error, 'reason should inherit Error');
+    assert_equals(reason.constructor, errorConstructor,
+                  'reason should have the right constructor');
+    assert_equals(reason.name, errorConstructor.name,
+                  `name should match constructor name`);
+    assert_equals(reason.message, 'nope', 'message should match');
+  }, `${errorConstructor.name} should be preserved`);
+}
+
+</script>