diff --git a/playwright/_impl/_element_handle.py b/playwright/_impl/_element_handle.py
index 23aec8994..5803413dc 100644
--- a/playwright/_impl/_element_handle.py
+++ b/playwright/_impl/_element_handle.py
@@ -19,8 +19,8 @@
 
 from playwright._impl._api_structures import FilePayload, FloatRect, Position
 from playwright._impl._connection import ChannelOwner, from_nullable_channel
-from playwright._impl._file_chooser import normalize_file_payloads
 from playwright._impl._helper import (
+    Error,
     KeyboardModifier,
     MouseButton,
     async_writefile,
@@ -33,6 +33,7 @@
     parse_result,
     serialize_argument,
 )
+from playwright._impl._set_input_files_helpers import convert_input_files
 
 if sys.version_info >= (3, 8):  # pragma: no cover
     from typing import Literal
@@ -190,8 +191,19 @@ async def set_input_files(
         noWaitAfter: bool = None,
     ) -> None:
         params = locals_to_params(locals())
-        params["files"] = await normalize_file_payloads(files)
-        await self._channel.send("setInputFiles", params)
+        frame = await self.owner_frame()
+        if not frame:
+            raise Error("Cannot set input files to detached element")
+        converted = await convert_input_files(files, frame.page.context)
+        if converted["files"] is not None:
+            await self._channel.send(
+                "setInputFiles", {**params, "files": converted["files"]}
+            )
+        else:
+            await self._channel.send(
+                "setInputFilePaths",
+                locals_to_params({**params, **converted, "files": None}),
+            )
 
     async def focus(self) -> None:
         await self._channel.send("focus")
diff --git a/playwright/_impl/_file_chooser.py b/playwright/_impl/_file_chooser.py
index 7add73e07..a15050fc0 100644
--- a/playwright/_impl/_file_chooser.py
+++ b/playwright/_impl/_file_chooser.py
@@ -12,13 +12,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import base64
-import os
 from pathlib import Path
 from typing import TYPE_CHECKING, List, Union
 
 from playwright._impl._api_structures import FilePayload
-from playwright._impl._helper import async_readfile
 
 if TYPE_CHECKING:  # pragma: no cover
     from playwright._impl._element_handle import ElementHandle
@@ -56,28 +53,3 @@ async def set_files(
         noWaitAfter: bool = None,
     ) -> None:
         await self._element_handle.set_input_files(files, timeout, noWaitAfter)
-
-
-async def normalize_file_payloads(
-    files: Union[str, Path, FilePayload, List[Union[str, Path]], List[FilePayload]]
-) -> List:
-    file_list = files if isinstance(files, list) else [files]
-    file_payloads: List = []
-    for item in file_list:
-        if isinstance(item, (str, Path)):
-            file_payloads.append(
-                {
-                    "name": os.path.basename(item),
-                    "buffer": base64.b64encode(await async_readfile(item)).decode(),
-                }
-            )
-        else:
-            file_payloads.append(
-                {
-                    "name": item["name"],
-                    "mimeType": item["mimeType"],
-                    "buffer": base64.b64encode(item["buffer"]).decode(),
-                }
-            )
-
-    return file_payloads
diff --git a/playwright/_impl/_frame.py b/playwright/_impl/_frame.py
index 9d6b272ce..471ea7dcb 100644
--- a/playwright/_impl/_frame.py
+++ b/playwright/_impl/_frame.py
@@ -28,7 +28,6 @@
 )
 from playwright._impl._element_handle import ElementHandle, convert_select_option_values
 from playwright._impl._event_context_manager import EventContextManagerImpl
-from playwright._impl._file_chooser import normalize_file_payloads
 from playwright._impl._helper import (
     DocumentLoadState,
     FrameNavigatedEvent,
@@ -48,6 +47,7 @@
 )
 from playwright._impl._locator import FrameLocator, Locator
 from playwright._impl._network import Response
+from playwright._impl._set_input_files_helpers import convert_input_files
 from playwright._impl._wait_helper import WaitHelper
 
 if sys.version_info >= (3, 8):  # pragma: no cover
@@ -598,8 +598,16 @@ async def set_input_files(
         noWaitAfter: bool = None,
     ) -> None:
         params = locals_to_params(locals())
-        params["files"] = await normalize_file_payloads(files)
-        await self._channel.send("setInputFiles", params)
+        converted = await convert_input_files(files, self.page.context)
+        if converted["files"] is not None:
+            await self._channel.send(
+                "setInputFiles", {**params, "files": converted["files"]}
+            )
+        else:
+            await self._channel.send(
+                "setInputFilePaths",
+                locals_to_params({**params, **converted, "files": None}),
+            )
 
     async def type(
         self,
diff --git a/playwright/_impl/_object_factory.py b/playwright/_impl/_object_factory.py
index a926d71ca..e04d1adec 100644
--- a/playwright/_impl/_object_factory.py
+++ b/playwright/_impl/_object_factory.py
@@ -33,6 +33,7 @@
 from playwright._impl._selectors import SelectorsOwner
 from playwright._impl._stream import Stream
 from playwright._impl._tracing import Tracing
+from playwright._impl._writable_stream import WritableStream
 
 
 class DummyObject(ChannelOwner):
@@ -89,6 +90,8 @@ def create_remote_object(
         return WebSocket(parent, type, guid, initializer)
     if type == "Worker":
         return Worker(parent, type, guid, initializer)
+    if type == "WritableStream":
+        return WritableStream(parent, type, guid, initializer)
     if type == "Selectors":
         return SelectorsOwner(parent, type, guid, initializer)
     return DummyObject(parent, type, guid, initializer)
diff --git a/playwright/_impl/_set_input_files_helpers.py b/playwright/_impl/_set_input_files_helpers.py
new file mode 100644
index 000000000..a03a41e91
--- /dev/null
+++ b/playwright/_impl/_set_input_files_helpers.py
@@ -0,0 +1,101 @@
+import base64
+import os
+import sys
+from pathlib import Path
+from typing import TYPE_CHECKING, List, Optional, Union
+
+if sys.version_info >= (3, 8):  # pragma: no cover
+    from typing import TypedDict
+else:  # pragma: no cover
+    from typing_extensions import TypedDict
+
+from playwright._impl._connection import Channel, from_channel
+from playwright._impl._helper import Error, async_readfile
+from playwright._impl._writable_stream import WritableStream
+
+if TYPE_CHECKING:  # pragma: no cover
+    from playwright._impl._browser_context import BrowserContext
+
+from playwright._impl._api_structures import FilePayload
+
+SIZE_LIMIT_IN_BYTES = 50 * 1024 * 1024
+
+
+class InputFilesList(TypedDict):
+    streams: Optional[List[Channel]]
+    localPaths: Optional[List[str]]
+    files: Optional[List[FilePayload]]
+
+
+async def convert_input_files(
+    files: Union[str, Path, FilePayload, List[Union[str, Path]], List[FilePayload]],
+    context: "BrowserContext",
+) -> InputFilesList:
+    file_list = files if isinstance(files, list) else [files]
+
+    has_large_buffer = any(
+        [
+            len(f.get("buffer", "")) > SIZE_LIMIT_IN_BYTES
+            for f in file_list
+            if not isinstance(f, (str, Path))
+        ]
+    )
+    if has_large_buffer:
+        raise Error(
+            "Cannot set buffer larger than 50Mb, please write it to a file and pass its path instead."
+        )
+
+    has_large_file = any(
+        [
+            os.stat(f).st_size > SIZE_LIMIT_IN_BYTES
+            for f in file_list
+            if isinstance(f, (str, Path))
+        ]
+    )
+    if has_large_file:
+        if context._channel._connection.is_remote:
+            streams = []
+            for file in file_list:
+                assert isinstance(file, (str, Path))
+                stream: WritableStream = from_channel(
+                    await context._channel.send(
+                        "createTempFile", {"name": os.path.basename(file)}
+                    )
+                )
+                await stream.copy(file)
+                streams.append(stream._channel)
+            return InputFilesList(streams=streams, localPaths=None, files=None)
+        local_paths = []
+        for p in file_list:
+            assert isinstance(p, (str, Path))
+            local_paths.append(str(Path(p).absolute().resolve()))
+        return InputFilesList(streams=None, localPaths=local_paths, files=None)
+
+    return InputFilesList(
+        streams=None, localPaths=None, files=await _normalize_file_payloads(files)
+    )
+
+
+async def _normalize_file_payloads(
+    files: Union[str, Path, FilePayload, List[Union[str, Path]], List[FilePayload]]
+) -> List:
+    file_list = files if isinstance(files, list) else [files]
+    file_payloads: List = []
+    for item in file_list:
+        if isinstance(item, (str, Path)):
+            file_payloads.append(
+                {
+                    "name": os.path.basename(item),
+                    "buffer": base64.b64encode(await async_readfile(item)).decode(),
+                }
+            )
+        else:
+            file_payloads.append(
+                {
+                    "name": item["name"],
+                    "mimeType": item["mimeType"],
+                    "buffer": base64.b64encode(item["buffer"]).decode(),
+                }
+            )
+
+    return file_payloads
diff --git a/playwright/_impl/_writable_stream.py b/playwright/_impl/_writable_stream.py
new file mode 100644
index 000000000..702adf153
--- /dev/null
+++ b/playwright/_impl/_writable_stream.py
@@ -0,0 +1,42 @@
+# Copyright (c) Microsoft Corporation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import base64
+import os
+from pathlib import Path
+from typing import Dict, Union
+
+from playwright._impl._connection import ChannelOwner
+
+# COPY_BUFSIZE is taken from shutil.py in the standard library
+_WINDOWS = os.name == "nt"
+COPY_BUFSIZE = 1024 * 1024 if _WINDOWS else 64 * 1024
+
+
+class WritableStream(ChannelOwner):
+    def __init__(
+        self, parent: ChannelOwner, type: str, guid: str, initializer: Dict
+    ) -> None:
+        super().__init__(parent, type, guid, initializer)
+
+    async def copy(self, path: Union[str, Path]) -> None:
+        with open(path, "rb") as f:
+            while True:
+                data = f.read(COPY_BUFSIZE)
+                if not data:
+                    break
+                await self._channel.send(
+                    "write", {"binary": base64.b64encode(data).decode()}
+                )
+        await self._channel.send("close")
diff --git a/setup.py b/setup.py
index d598e5d69..5d8e764b5 100644
--- a/setup.py
+++ b/setup.py
@@ -30,7 +30,7 @@
     InWheel = None
 from wheel.bdist_wheel import bdist_wheel as BDistWheelCommand
 
-driver_version = "1.21.0-beta-1649712128000"
+driver_version = "1.21.0"
 
 
 def extractall(zip: zipfile.ZipFile, path: str) -> None:
diff --git a/tests/assets/input/fileupload.html b/tests/assets/input/fileupload.html
index 57e90d50a..771dc4c68 100644
--- a/tests/assets/input/fileupload.html
+++ b/tests/assets/input/fileupload.html
@@ -4,8 +4,8 @@
     <title>File upload test</title>
   </head>
   <body>
-    <form action="/input/fileupload.html">
-      <input type="file">
+    <form action="/upload" method="post" enctype="multipart/form-data">
+      <input type="file" name="file1">
       <input type="submit">
     </form>
   </body>
diff --git a/tests/async/test_add_init_script.py b/tests/async/test_add_init_script.py
index 7317e7523..515891a88 100644
--- a/tests/async/test_add_init_script.py
+++ b/tests/async/test_add_init_script.py
@@ -74,3 +74,10 @@ async def test_add_init_script_support_multiple_scripts(page):
     await page.goto("data:text/html,<script>window.result = window.injected</script>")
     assert await page.evaluate("window.script1") == 1
     assert await page.evaluate("window.script2") == 2
+
+
+async def test_should_work_with_trailing_comments(page):
+    await page.add_init_script("// comment")
+    await page.add_init_script("window.secret = 42;")
+    await page.goto("data:text/html,<html></html>")
+    assert await page.evaluate("secret") == 42
diff --git a/tests/async/test_browsertype_connect.py b/tests/async/test_browsertype_connect.py
index 73ab81c0b..9dce38780 100644
--- a/tests/async/test_browsertype_connect.py
+++ b/tests/async/test_browsertype_connect.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import asyncio
+import re
 from typing import Callable
 
 import pytest
@@ -241,3 +243,58 @@ async def handle_request(route: Route) -> None:
     assert await response.json() == {"foo": "bar"}
 
     remote.kill()
+
+
+@pytest.mark.only_browser("chromium")
+async def test_should_upload_large_file(
+    browser_type: BrowserType,
+    launch_server: Callable[[], RemoteServer],
+    playwright: Playwright,
+    server: Server,
+    tmp_path,
+):
+    remote = launch_server()
+
+    browser = await browser_type.connect(remote.ws_endpoint)
+    context = await browser.new_context()
+    page = await context.new_page()
+
+    await page.goto(server.PREFIX + "/input/fileupload.html")
+    large_file_path = tmp_path / "200MB.zip"
+    data = b"A" * 1024
+    with large_file_path.open("wb") as f:
+        for i in range(0, 200 * 1024 * 1024, len(data)):
+            f.write(data)
+    input = page.locator('input[type="file"]')
+    events = await input.evaluate_handle(
+        """
+        e => {
+            const events = [];
+            e.addEventListener('input', () => events.push('input'));
+            e.addEventListener('change', () => events.push('change'));
+            return events;
+        }
+    """
+    )
+
+    await input.set_input_files(large_file_path)
+    assert await input.evaluate("e => e.files[0].name") == "200MB.zip"
+    assert await events.evaluate("e => e") == ["input", "change"]
+
+    [request, _] = await asyncio.gather(
+        server.wait_for_request("/upload"),
+        page.click("input[type=submit]"),
+    )
+
+    contents = request.args[b"file1"][0]
+    assert len(contents) == 200 * 1024 * 1024
+    assert contents[:1024] == data
+    # flake8: noqa: E203
+    assert contents[len(contents) - 1024 :] == data
+    match = re.search(
+        rb'^.*Content-Disposition: form-data; name="(?P<name>.*)"; filename="(?P<filename>.*)".*$',
+        request.post_body,
+        re.MULTILINE,
+    )
+    assert match.group("name") == b"file1"
+    assert match.group("filename") == b"200MB.zip"
diff --git a/tests/async/test_input.py b/tests/async/test_input.py
index 3ff92ebe6..77e0ca1c8 100644
--- a/tests/async/test_input.py
+++ b/tests/async/test_input.py
@@ -14,6 +14,7 @@
 
 import asyncio
 import os
+import re
 
 import pytest
 
@@ -284,3 +285,46 @@ async def _listen_for_wheel_events(page: Page, selector: str) -> None:
     """,
         selector,
     )
+
+
+@pytest.mark.only_browser("chromium")
+async def test_should_upload_large_file(page, server, tmp_path):
+    await page.goto(server.PREFIX + "/input/fileupload.html")
+    large_file_path = tmp_path / "200MB.zip"
+    data = b"A" * 1024
+    with large_file_path.open("wb") as f:
+        for i in range(0, 200 * 1024 * 1024, len(data)):
+            f.write(data)
+    input = page.locator('input[type="file"]')
+    events = await input.evaluate_handle(
+        """
+        e => {
+            const events = [];
+            e.addEventListener('input', () => events.push('input'));
+            e.addEventListener('change', () => events.push('change'));
+            return events;
+        }
+    """
+    )
+
+    await input.set_input_files(large_file_path)
+    assert await input.evaluate("e => e.files[0].name") == "200MB.zip"
+    assert await events.evaluate("e => e") == ["input", "change"]
+
+    [request, _] = await asyncio.gather(
+        server.wait_for_request("/upload"),
+        page.click("input[type=submit]"),
+    )
+
+    contents = request.args[b"file1"][0]
+    assert len(contents) == 200 * 1024 * 1024
+    assert contents[:1024] == data
+    # flake8: noqa: E203
+    assert contents[len(contents) - 1024 :] == data
+    match = re.search(
+        rb'^.*Content-Disposition: form-data; name="(?P<name>.*)"; filename="(?P<filename>.*)".*$',
+        request.post_body,
+        re.MULTILINE,
+    )
+    assert match.group("name") == b"file1"
+    assert match.group("filename") == b"200MB.zip"
diff --git a/tests/sync/test_add_init_script.py b/tests/sync/test_add_init_script.py
index 5fc626a18..039862063 100644
--- a/tests/sync/test_add_init_script.py
+++ b/tests/sync/test_add_init_script.py
@@ -78,3 +78,10 @@ def test_add_init_script_support_multiple_scripts(page: Page) -> None:
     page.goto("data:text/html,<script>window.result = window.injected</script>")
     assert page.evaluate("window.script1") == 1
     assert page.evaluate("window.script2") == 2
+
+
+def test_should_work_with_trailing_comments(page: Page) -> None:
+    page.add_init_script("// comment")
+    page.add_init_script("window.secret = 42;")
+    page.goto("data:text/html,<html></html>")
+    assert page.evaluate("secret") == 42