diff --git a/dotnet/src/webdriver/BiDi/Communication/Broker.cs b/dotnet/src/webdriver/BiDi/Communication/Broker.cs
index f0c0f2c279f91..db2058224749b 100644
--- a/dotnet/src/webdriver/BiDi/Communication/Broker.cs
+++ b/dotnet/src/webdriver/BiDi/Communication/Broker.cs
@@ -84,7 +84,6 @@ internal Broker(BiDi bidi, Uri url)
                 new RealmConverter(_bidi),
                 new RealmTypeConverter(),
                 new DateTimeOffsetConverter(),
-                new TimeSpanConverter(),
                 new PrintPageRangeConverter(),
                 new InputOriginConverter(),
                 new WebExtensionConverter(_bidi),
diff --git a/dotnet/src/webdriver/BiDi/Communication/Json/Converters/DateTimeOffsetConverter.cs b/dotnet/src/webdriver/BiDi/Communication/Json/Converters/DateTimeOffsetConverter.cs
index e3b2b57ffe4f4..4ffa57f627bba 100644
--- a/dotnet/src/webdriver/BiDi/Communication/Json/Converters/DateTimeOffsetConverter.cs
+++ b/dotnet/src/webdriver/BiDi/Communication/Json/Converters/DateTimeOffsetConverter.cs
@@ -27,7 +27,16 @@ internal class DateTimeOffsetConverter : JsonConverter<DateTimeOffset>
 {
     public override DateTimeOffset Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
     {
-        return DateTimeOffset.FromUnixTimeMilliseconds(reader.GetInt64());
+        // Workaround: it should be Int64, chrome uses double for `expiry` like "expiry":1737379944.308351
+
+        if (reader.TryGetInt64(out long unixTime) is false)
+        {
+            var doubleValue = reader.GetDouble();
+
+            unixTime = Convert.ToInt64(doubleValue);
+        }
+
+        return DateTimeOffset.FromUnixTimeMilliseconds(unixTime);
     }
 
     public override void Write(Utf8JsonWriter writer, DateTimeOffset value, JsonSerializerOptions options)
diff --git a/dotnet/src/webdriver/BiDi/Communication/Json/Converters/TimeSpanConverter.cs b/dotnet/src/webdriver/BiDi/Communication/Json/Converters/TimeSpanConverter.cs
deleted file mode 100644
index 8bb6717f2391c..0000000000000
--- a/dotnet/src/webdriver/BiDi/Communication/Json/Converters/TimeSpanConverter.cs
+++ /dev/null
@@ -1,44 +0,0 @@
-// <copyright file="TimeSpanConverter.cs" company="Selenium Committers">
-// Licensed to the Software Freedom Conservancy (SFC) under one
-// or more contributor license agreements.  See the NOTICE file
-// distributed with this work for additional information
-// regarding copyright ownership.  The SFC licenses this file
-// to you 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.
-// </copyright>
-
-using System;
-using System.Text.Json;
-using System.Text.Json.Serialization;
-
-namespace OpenQA.Selenium.BiDi.Communication.Json.Converters;
-
-internal class TimeSpanConverter : JsonConverter<TimeSpan>
-{
-    public override TimeSpan Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
-    {
-        if (reader.TryGetInt64(out long milliseconds) is false)
-        {
-            var doubleValue = reader.GetDouble();
-
-            milliseconds = Convert.ToInt64(doubleValue);
-        }
-
-        return TimeSpan.FromMilliseconds(milliseconds);
-    }
-
-    public override void Write(Utf8JsonWriter writer, TimeSpan value, JsonSerializerOptions options)
-    {
-        writer.WriteNumberValue(value.TotalMilliseconds);
-    }
-}
diff --git a/dotnet/src/webdriver/BiDi/Network/Cookie.cs b/dotnet/src/webdriver/BiDi/Network/Cookie.cs
index 972e02541f1d8..226f03ec36e64 100644
--- a/dotnet/src/webdriver/BiDi/Network/Cookie.cs
+++ b/dotnet/src/webdriver/BiDi/Network/Cookie.cs
@@ -18,10 +18,15 @@
 // </copyright>
 
 using System;
+using System.Text.Json.Serialization;
 
 namespace OpenQA.Selenium.BiDi.Network;
 
-public sealed record Cookie(string Name, BytesValue Value, string Domain, string Path, long Size, bool HttpOnly, bool Secure, SameSite SameSite, TimeSpan? Expiry);
+public sealed record Cookie(string Name, BytesValue Value, string Domain, string Path, long Size, bool HttpOnly, bool Secure, SameSite SameSite)
+{
+    [JsonInclude]
+    public DateTimeOffset? Expiry { get; internal set; }
+}
 
 public enum SameSite
 {