diff --git a/test/fixtures/wpt/README.md b/test/fixtures/wpt/README.md
index 406e89b820e9f7..8336539a7d70d4 100644
--- a/test/fixtures/wpt/README.md
+++ b/test/fixtures/wpt/README.md
@@ -27,7 +27,7 @@ Last update:
 - performance-timeline: https://github.com/web-platform-tests/wpt/tree/94caab7038/performance-timeline
 - resource-timing: https://github.com/web-platform-tests/wpt/tree/22d38586d0/resource-timing
 - resources: https://github.com/web-platform-tests/wpt/tree/1e140d63ec/resources
-- streams: https://github.com/web-platform-tests/wpt/tree/2bd26e124c/streams
+- streams: https://github.com/web-platform-tests/wpt/tree/bc9dcbbf1a/streams
 - url: https://github.com/web-platform-tests/wpt/tree/67880a4eb8/url
 - user-timing: https://github.com/web-platform-tests/wpt/tree/5ae85bf826/user-timing
 - wasm/jsapi: https://github.com/web-platform-tests/wpt/tree/cde25e7e3c/wasm/jsapi
diff --git a/test/fixtures/wpt/streams/idlharness-shadowrealm.window.js b/test/fixtures/wpt/streams/idlharness-shadowrealm.window.js
deleted file mode 100644
index 099b2475ca7e87..00000000000000
--- a/test/fixtures/wpt/streams/idlharness-shadowrealm.window.js
+++ /dev/null
@@ -1,2 +0,0 @@
-// META: script=/resources/idlharness-shadowrealm.js
-idl_test_shadowrealm(["streams"], ["dom"]);
diff --git a/test/fixtures/wpt/streams/idlharness.any.js b/test/fixtures/wpt/streams/idlharness.any.js
index 42a17da58c5ae3..0be03b2078f9bc 100644
--- a/test/fixtures/wpt/streams/idlharness.any.js
+++ b/test/fixtures/wpt/streams/idlharness.any.js
@@ -1,4 +1,4 @@
-// META: global=window,worker
+// META: global=window,worker,shadowrealm-in-window
 // META: script=/resources/WebIDLParser.js
 // META: script=/resources/idlharness.js
 // META: timeout=long
diff --git a/test/fixtures/wpt/streams/readable-byte-streams/general.any.js b/test/fixtures/wpt/streams/readable-byte-streams/general.any.js
index cdce2244c3c84b..4b0c73865f7cf9 100644
--- a/test/fixtures/wpt/streams/readable-byte-streams/general.any.js
+++ b/test/fixtures/wpt/streams/readable-byte-streams/general.any.js
@@ -870,11 +870,11 @@ promise_test(() => {
     start(c) {
       controller = c;
     },
-    async pull() {
+    pull() {
       byobRequestDefined.push(controller.byobRequest !== null);
       const initialByobRequest = controller.byobRequest;
 
-      const transferredView = await transferArrayBufferView(controller.byobRequest.view);
+      const transferredView = transferArrayBufferView(controller.byobRequest.view);
       transferredView[0] = 0x01;
       controller.byobRequest.respondWithNewView(transferredView);
 
@@ -2288,7 +2288,7 @@ promise_test(async t => {
   await pullCalledPromise;
 
   // Transfer the original BYOB request's buffer, and respond with a new view on that buffer
-  const transferredView = await transferArrayBufferView(controller.byobRequest.view);
+  const transferredView = transferArrayBufferView(controller.byobRequest.view);
   const newView = transferredView.subarray(0, 1);
   newView[0] = 42;
 
@@ -2328,7 +2328,7 @@ promise_test(async t => {
   await pullCalledPromise;
 
   // Transfer the original BYOB request's buffer, and respond with an empty view on that buffer
-  const transferredView = await transferArrayBufferView(controller.byobRequest.view);
+  const transferredView = transferArrayBufferView(controller.byobRequest.view);
   const newView = transferredView.subarray(0, 0);
 
   controller.close();
diff --git a/test/fixtures/wpt/streams/readable-byte-streams/patched-global.any.js b/test/fixtures/wpt/streams/readable-byte-streams/patched-global.any.js
new file mode 100644
index 00000000000000..ce2e9e9993ae57
--- /dev/null
+++ b/test/fixtures/wpt/streams/readable-byte-streams/patched-global.any.js
@@ -0,0 +1,54 @@
+// META: global=window,worker,shadowrealm
+// META: script=../resources/test-utils.js
+'use strict';
+
+// Tests which patch the global environment are kept separate to avoid
+// interfering with other tests.
+
+promise_test(async (t) => {
+  let controller;
+  const rs = new ReadableStream({
+    type: 'bytes',
+    start(c) {
+      controller = c;
+    }
+  });
+  const reader = rs.getReader({mode: 'byob'});
+
+  const length = 0x4000;
+  const buffer = new ArrayBuffer(length);
+  const bigArray = new BigUint64Array(buffer, length - 8, 1);
+
+  const read1 = reader.read(new Uint8Array(new ArrayBuffer(0x100)));
+  const read2 = reader.read(bigArray);
+
+  let flag = false;
+  Object.defineProperty(Object.prototype, 'then', {
+    get: t.step_func(() => {
+      if (!flag) {
+        flag = true;
+        assert_equals(controller.byobRequest, null, 'byobRequest should be null after filling both views');
+      }
+    }),
+    configurable: true
+  });
+  t.add_cleanup(() => {
+    delete Object.prototype.then;
+  });
+
+  controller.enqueue(new Uint8Array(0x110).fill(0x42));
+  assert_true(flag, 'patched then() should be called');
+
+  // The first read() is filled entirely with 0x100 bytes
+  const result1 = await read1;
+  assert_false(result1.done, 'result1.done');
+  assert_typed_array_equals(result1.value, new Uint8Array(0x100).fill(0x42), 'result1.value');
+
+  // The second read() is filled with the remaining 0x10 bytes
+  const result2 = await read2;
+  assert_false(result2.done, 'result2.done');
+  assert_equals(result2.value.constructor, BigUint64Array, 'result2.value constructor');
+  assert_equals(result2.value.byteOffset, length - 8, 'result2.value byteOffset');
+  assert_equals(result2.value.length, 1, 'result2.value length');
+  assert_array_equals([...result2.value], [0x42424242_42424242n], 'result2.value contents');
+}, 'Patched then() sees byobRequest after filling all pending pull-into descriptors');
diff --git a/test/fixtures/wpt/streams/readable-byte-streams/tee.any.js b/test/fixtures/wpt/streams/readable-byte-streams/tee.any.js
index 7dd5ba3f3fb013..60d82b9cf6a1fd 100644
--- a/test/fixtures/wpt/streams/readable-byte-streams/tee.any.js
+++ b/test/fixtures/wpt/streams/readable-byte-streams/tee.any.js
@@ -934,3 +934,36 @@ promise_test(async () => {
   assert_typed_array_equals(result4.value, new Uint8Array([0]).subarray(0, 0), 'second chunk from branch2 should be correct');
 
 }, 'ReadableStream teeing with byte source: respond() and close() while both branches are pulling');
+
+promise_test(async t => {
+  let pullCount = 0;
+  const arrayBuffer = new Uint8Array([0x01, 0x02, 0x03]).buffer;
+  const enqueuedChunk = new Uint8Array(arrayBuffer, 2);
+  assert_equals(enqueuedChunk.length, 1);
+  assert_equals(enqueuedChunk.byteOffset, 2);
+  const rs = new ReadableStream({
+    type: 'bytes',
+    pull(c) {
+      ++pullCount;
+      if (pullCount === 1) {
+        c.enqueue(enqueuedChunk);
+      }
+    }
+  });
+
+  const [branch1, branch2] = rs.tee();
+  const reader1 = branch1.getReader();
+  const reader2 = branch2.getReader();
+
+  const [result1, result2] = await Promise.all([reader1.read(), reader2.read()]);
+  assert_equals(result1.done, false, 'reader1 done');
+  assert_equals(result2.done, false, 'reader2 done');
+
+  const view1 = result1.value;
+  const view2 = result2.value;
+  // The first stream has the transferred buffer, but the second stream has the
+  // cloned buffer.
+  const underlying = new Uint8Array([0x01, 0x02, 0x03]).buffer;
+  assert_typed_array_equals(view1, new Uint8Array(underlying, 2), 'reader1 value');
+  assert_typed_array_equals(view2, new Uint8Array([0x03]), 'reader2 value');
+}, 'ReadableStream teeing with byte source: reading an array with a byte offset should clone correctly');
diff --git a/test/fixtures/wpt/streams/readable-streams/crashtests/from-cross-realm.https.html b/test/fixtures/wpt/streams/readable-streams/crashtests/from-cross-realm.https.html
new file mode 100644
index 00000000000000..58a4371186ece7
--- /dev/null
+++ b/test/fixtures/wpt/streams/readable-streams/crashtests/from-cross-realm.https.html
@@ -0,0 +1,18 @@
+<html class="test-wait">
+<meta charset="utf-8">
+<script type="module">
+  let a = window.open()
+  try {
+    let dir = await a.navigator.storage.getDirectory()
+    let hdl = await dir.getFileHandle("7399d8cf-9ff9-494d-89eb-d3045f229c27", {"create": true})
+    let map = new Map([[]])
+    let b = ReadableStream.from(map)
+    let c = await hdl.createWritable({ })
+    await b.pipeTo(c, { }).catch(() => {
+      // Error expected as we are not piping the right form of chunk to FileHandle
+    })
+  } finally {
+    document.documentElement.classList.remove("test-wait")
+    a.close()
+  }
+</script>
diff --git a/test/fixtures/wpt/streams/readable-streams/owning-type-video-frame.any.js b/test/fixtures/wpt/streams/readable-streams/owning-type-video-frame.any.js
index b652f9c5fcb4b6..ec01fda0b3c737 100644
--- a/test/fixtures/wpt/streams/readable-streams/owning-type-video-frame.any.js
+++ b/test/fixtures/wpt/streams/readable-streams/owning-type-video-frame.any.js
@@ -1,4 +1,4 @@
-// META: global=window,worker,shadowrealm
+// META: global=window,worker
 // META: script=../resources/test-utils.js
 // META: script=../resources/rs-utils.js
 'use strict';
diff --git a/test/fixtures/wpt/streams/resources/rs-utils.js b/test/fixtures/wpt/streams/resources/rs-utils.js
index f1a014275a2fbc..0f7742a5b3b190 100644
--- a/test/fixtures/wpt/streams/resources/rs-utils.js
+++ b/test/fixtures/wpt/streams/resources/rs-utils.js
@@ -1,5 +1,42 @@
 'use strict';
 (function () {
+  // Fake setInterval-like functionality in environments that don't have it
+  class IntervalHandle {
+    constructor(callback, delayMs) {
+      this.callback = callback;
+      this.delayMs = delayMs;
+      this.cancelled = false;
+      Promise.resolve().then(() => this.check());
+    }
+
+    async check() {
+      while (true) {
+        await new Promise(resolve => step_timeout(resolve, this.delayMs));
+        if (this.cancelled) {
+          return;
+        }
+        this.callback();
+      }
+    }
+
+    cancel() {
+      this.cancelled = true;
+    }
+  }
+
+  let localSetInterval, localClearInterval;
+  if (typeof globalThis.setInterval !== "undefined" &&
+      typeof globalThis.clearInterval !== "undefined") {
+    localSetInterval = globalThis.setInterval;
+    localClearInterval = globalThis.clearInterval;
+  } else {
+    localSetInterval = function setInterval(callback, delayMs) {
+      return new IntervalHandle(callback, delayMs);
+    }
+    localClearInterval = function clearInterval(handle) {
+      handle.cancel();
+    }
+  }
 
   class RandomPushSource {
     constructor(toPush) {
@@ -18,12 +55,12 @@
       }
 
       if (!this.started) {
-        this._intervalHandle = setInterval(writeChunk, 2);
+        this._intervalHandle = localSetInterval(writeChunk, 2);
         this.started = true;
       }
 
       if (this.paused) {
-        this._intervalHandle = setInterval(writeChunk, 2);
+        this._intervalHandle = localSetInterval(writeChunk, 2);
         this.paused = false;
       }
 
@@ -37,7 +74,7 @@
 
         if (source.toPush > 0 && source.pushed > source.toPush) {
           if (source._intervalHandle) {
-            clearInterval(source._intervalHandle);
+            localClearInterval(source._intervalHandle);
             source._intervalHandle = undefined;
           }
           source.closed = true;
@@ -55,7 +92,7 @@
 
       if (this.started) {
         this.paused = true;
-        clearInterval(this._intervalHandle);
+        localClearInterval(this._intervalHandle);
         this._intervalHandle = undefined;
       } else {
         throw new Error('Can\'t pause reading an unstarted source.');
@@ -178,15 +215,7 @@
   }
 
   function transferArrayBufferView(view) {
-    const noopByteStream = new ReadableStream({
-      type: 'bytes',
-      pull(c) {
-        c.byobRequest.respond(c.byobRequest.view.byteLength);
-        c.close();
-      }
-    });
-    const reader = noopByteStream.getReader({ mode: 'byob' });
-    return reader.read(view).then((result) => result.value);
+    return structuredClone(view, { transfer: [view.buffer] });
   }
 
   self.RandomPushSource = RandomPushSource;
diff --git a/test/fixtures/wpt/streams/transferable/transfer-with-messageport.window.js b/test/fixtures/wpt/streams/transferable/transfer-with-messageport.window.js
index 37f8c9df169607..3bfe634a6e153d 100644
--- a/test/fixtures/wpt/streams/transferable/transfer-with-messageport.window.js
+++ b/test/fixtures/wpt/streams/transferable/transfer-with-messageport.window.js
@@ -105,7 +105,7 @@ async function transferMessagePortWith(constructor) {
   await transferMessagePortWithOrder3(new constructor());
 }
 
-async function advancedTransferMesagePortWith(constructor) {
+async function advancedTransferMessagePortWith(constructor) {
   await transferMessagePortWithOrder4(new constructor());
   await transferMessagePortWithOrder5(new constructor());
   await transferMessagePortWithOrder6(new constructor());
@@ -166,7 +166,7 @@ async function mixedTransferMessagePortWithOrder3() {
   );
 }
 
-async function mixedTransferMesagePortWith() {
+async function mixedTransferMessagePortWith() {
   await mixedTransferMessagePortWithOrder1();
   await mixedTransferMessagePortWithOrder2();
   await mixedTransferMessagePortWithOrder3();
@@ -185,19 +185,19 @@ promise_test(async t => {
 }, "Transferring a MessagePort with a TransformStream should set `.ports`");
 
 promise_test(async t => {
-  await transferMessagePortWith(ReadableStream);
+  await advancedTransferMessagePortWith(ReadableStream);
 }, "Transferring a MessagePort with a ReadableStream should set `.ports`, advanced");
 
 promise_test(async t => {
-  await transferMessagePortWith(WritableStream);
+  await advancedTransferMessagePortWith(WritableStream);
 }, "Transferring a MessagePort with a WritableStream should set `.ports`, advanced");
 
 promise_test(async t => {
-  await transferMessagePortWith(TransformStream);
+  await advancedTransferMessagePortWith(TransformStream);
 }, "Transferring a MessagePort with a TransformStream should set `.ports`, advanced");
 
 promise_test(async t => {
-  await mixedTransferMesagePortWith();
+  await mixedTransferMessagePortWith();
 }, "Transferring a MessagePort with multiple streams should set `.ports`");
 
 test(() => {
diff --git a/test/fixtures/wpt/versions.json b/test/fixtures/wpt/versions.json
index 55227b3be66e1b..a3e0dd60ed66ab 100644
--- a/test/fixtures/wpt/versions.json
+++ b/test/fixtures/wpt/versions.json
@@ -68,7 +68,7 @@
     "path": "resources"
   },
   "streams": {
-    "commit": "2bd26e124cf17b2f0a25c150794d640b07b2a870",
+    "commit": "bc9dcbbf1a4c2c741ef47f47d6ede6458f40c4a4",
     "path": "streams"
   },
   "url": {