diff --git a/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs b/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
index c641b760b6..6d7c5ac6ee 100644
--- a/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
+++ b/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
@@ -10,7 +10,6 @@ using System.Net.Http;
 using System.Net.Mime;
 using System.Text;
 using System.Text.Json;
-using System.Text.Json.Serialization;
 using System.Threading;
 using System.Threading.Tasks;
 using MediaBrowser.Common;
diff --git a/Emby.Server.Implementations/Session/WebSocketController.cs b/Emby.Server.Implementations/Session/WebSocketController.cs
index f9c6a13c69..a653b58c2b 100644
--- a/Emby.Server.Implementations/Session/WebSocketController.cs
+++ b/Emby.Server.Implementations/Session/WebSocketController.cs
@@ -8,7 +8,6 @@ using System.Linq;
 using System.Net.WebSockets;
 using System.Threading;
 using System.Threading.Tasks;
-using MediaBrowser.Common.Extensions;
 using MediaBrowser.Controller.Net;
 using MediaBrowser.Controller.Session;
 using MediaBrowser.Model.Net;
diff --git a/Jellyfin.Api/Extensions/DtoExtensions.cs b/Jellyfin.Api/Extensions/DtoExtensions.cs
index f2abd515d3..e0c744325f 100644
--- a/Jellyfin.Api/Extensions/DtoExtensions.cs
+++ b/Jellyfin.Api/Extensions/DtoExtensions.cs
@@ -113,14 +113,5 @@ namespace Jellyfin.Api.Extensions
 
             return dtoOptions;
         }
-
-        /// <summary>
-        /// Check if DtoOptions contains field.
-        /// </summary>
-        /// <param name="dtoOptions">DtoOptions object.</param>
-        /// <param name="field">Field to check.</param>
-        /// <returns>Field existence.</returns>
-        internal static bool ContainsField(this DtoOptions dtoOptions, ItemFields field)
-            => dtoOptions.Fields != null && dtoOptions.Fields.Contains(field);
     }
 }
diff --git a/Jellyfin.Api/Helpers/DynamicHlsHelper.cs b/Jellyfin.Api/Helpers/DynamicHlsHelper.cs
index 8a47f7461d..16380f0bba 100644
--- a/Jellyfin.Api/Helpers/DynamicHlsHelper.cs
+++ b/Jellyfin.Api/Helpers/DynamicHlsHelper.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Net;
+using System.Net.Mime;
 using System.Security.Claims;
 using System.Text;
 using System.Threading;
@@ -171,13 +172,15 @@ namespace Jellyfin.Api.Helpers
             var queryString = _httpContextAccessor.HttpContext.Request.QueryString.ToString();
 
             // from universal audio service
-            if (queryString.IndexOf("SegmentContainer", StringComparison.OrdinalIgnoreCase) == -1 && !string.IsNullOrWhiteSpace(state.Request.SegmentContainer))
+            if (!string.IsNullOrWhiteSpace(state.Request.SegmentContainer)
+                && !queryString.Contains("SegmentContainer", StringComparison.OrdinalIgnoreCase))
             {
                 queryString += "&SegmentContainer=" + state.Request.SegmentContainer;
             }
 
             // from universal audio service
-            if (!string.IsNullOrWhiteSpace(state.Request.TranscodeReasons) && queryString.IndexOf("TranscodeReasons=", StringComparison.OrdinalIgnoreCase) == -1)
+            if (!string.IsNullOrWhiteSpace(state.Request.TranscodeReasons)
+                && !queryString.Contains("TranscodeReasons=", StringComparison.OrdinalIgnoreCase))
             {
                 queryString += "&TranscodeReasons=" + state.Request.TranscodeReasons;
             }
@@ -560,13 +563,13 @@ namespace Jellyfin.Api.Helpers
                 profileString = state.GetRequestedProfiles(codec).FirstOrDefault() ?? string.Empty;
                 if (string.Equals(state.ActualOutputVideoCodec, "h264", StringComparison.OrdinalIgnoreCase))
                 {
-                    profileString = profileString ?? "high";
+                    profileString ??= "high";
                 }
 
                 if (string.Equals(state.ActualOutputVideoCodec, "h265", StringComparison.OrdinalIgnoreCase)
                     || string.Equals(state.ActualOutputVideoCodec, "hevc", StringComparison.OrdinalIgnoreCase))
                 {
-                    profileString = profileString ?? "main";
+                    profileString ??= "main";
                 }
             }
 
diff --git a/Jellyfin.Api/Helpers/StreamingHelpers.cs b/Jellyfin.Api/Helpers/StreamingHelpers.cs
index 4957ee8b8d..153ec31759 100644
--- a/Jellyfin.Api/Helpers/StreamingHelpers.cs
+++ b/Jellyfin.Api/Helpers/StreamingHelpers.cs
@@ -245,7 +245,7 @@ namespace Jellyfin.Api.Helpers
 
             var ext = string.IsNullOrWhiteSpace(state.OutputContainer)
                 ? GetOutputFileExtension(state)
-                : ('.' + state.OutputContainer);
+                : ("." + state.OutputContainer);
 
             state.OutputFilePath = GetOutputFilePath(state, ext!, serverConfigurationManager, streamingRequest.DeviceId, streamingRequest.PlaySessionId);
 
diff --git a/MediaBrowser.Common/Extensions/StringExtensions.cs b/MediaBrowser.Common/Extensions/StringExtensions.cs
deleted file mode 100644
index 7643017412..0000000000
--- a/MediaBrowser.Common/Extensions/StringExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-#nullable enable
-
-using System;
-
-namespace MediaBrowser.Common.Extensions
-{
-    /// <summary>
-    /// Extensions methods to simplify string operations.
-    /// </summary>
-    public static class StringExtensions
-    {
-        /// <summary>
-        /// Returns the part on the left of the <c>needle</c>.
-        /// </summary>
-        /// <param name="haystack">The string to seek.</param>
-        /// <param name="needle">The needle to find.</param>
-        /// <returns>The part left of the <paramref name="needle" />.</returns>
-        public static ReadOnlySpan<char> LeftPart(this ReadOnlySpan<char> haystack, char needle)
-        {
-            var pos = haystack.IndexOf(needle);
-            return pos == -1 ? haystack : haystack[..pos];
-        }
-
-        /// <summary>
-        /// Returns the part on the left of the <c>needle</c>.
-        /// </summary>
-        /// <param name="haystack">The string to seek.</param>
-        /// <param name="needle">The needle to find.</param>
-        /// <param name="stringComparison">One of the enumeration values that specifies the rules for the search.</param>
-        /// <returns>The part left of the <c>needle</c>.</returns>
-        public static ReadOnlySpan<char> LeftPart(this ReadOnlySpan<char> haystack, ReadOnlySpan<char> needle, StringComparison stringComparison = default)
-        {
-            var pos = haystack.IndexOf(needle, stringComparison);
-            return pos == -1 ? haystack : haystack[..pos];
-        }
-    }
-}
diff --git a/MediaBrowser.Common/Net/NetworkExtensions.cs b/MediaBrowser.Common/Net/NetworkExtensions.cs
index d07bba249b..9c1a0cf495 100644
--- a/MediaBrowser.Common/Net/NetworkExtensions.cs
+++ b/MediaBrowser.Common/Net/NetworkExtensions.cs
@@ -1,11 +1,6 @@
-#pragma warning disable CA1062 // Validate arguments of public methods
 using System;
-using System.Collections;
-using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Net;
-using System.Runtime.CompilerServices;
-using System.Text;
 
 namespace MediaBrowser.Common.Net
 {
diff --git a/tests/Jellyfin.Api.Tests/ParseNetworkTests.cs b/tests/Jellyfin.Api.Tests/ParseNetworkTests.cs
index 6c3fd0ee10..3984407ee9 100644
--- a/tests/Jellyfin.Api.Tests/ParseNetworkTests.cs
+++ b/tests/Jellyfin.Api.Tests/ParseNetworkTests.cs
@@ -37,28 +37,28 @@ namespace Jellyfin.Api.Tests
                 EnableIPV6 = ip6
             };
 
-            var result = match + ',';
+            var result = match + ",";
             ForwardedHeadersOptions options = new ForwardedHeadersOptions();
 
             // Need this here as ::1 and 127.0.0.1 are in them by default.
             options.KnownProxies.Clear();
             options.KnownNetworks.Clear();
 
-            ApiServiceCollectionExtensions.AddProxyAddresses(settings, hostList.Split(","), options);
+            ApiServiceCollectionExtensions.AddProxyAddresses(settings, hostList.Split(','), options);
 
             var sb = new StringBuilder();
             foreach (var item in options.KnownProxies)
             {
-                sb.Append(item);
-                sb.Append(',');
+                sb.Append(item)
+                    .Append(',');
             }
 
             foreach (var item in options.KnownNetworks)
             {
-                sb.Append(item.Prefix);
-                sb.Append('/');
-                sb.Append(item.PrefixLength.ToString(CultureInfo.InvariantCulture));
-                sb.Append(',');
+                sb.Append(item.Prefix)
+                    .Append('/')
+                    .Append(item.PrefixLength.ToString(CultureInfo.InvariantCulture))
+                    .Append(',');
             }
 
             Assert.Equal(sb.ToString(), result);
diff --git a/tests/Jellyfin.Common.Tests/Extensions/StringExtensionsTests.cs b/tests/Jellyfin.Common.Tests/Extensions/StringExtensionsTests.cs
deleted file mode 100644
index 8bf613f05f..0000000000
--- a/tests/Jellyfin.Common.Tests/Extensions/StringExtensionsTests.cs
+++ /dev/null
@@ -1,43 +0,0 @@
-using System;
-using MediaBrowser.Common.Extensions;
-using Xunit;
-
-namespace Jellyfin.Common.Tests.Extensions
-{
-    public class StringExtensionsTests
-    {
-        [Theory]
-        [InlineData("", 'q', "")]
-        [InlineData("Banana split", ' ', "Banana")]
-        [InlineData("Banana split", 'q', "Banana split")]
-        public void LeftPart_ValidArgsCharNeedle_Correct(string str, char needle, string expectedResult)
-        {
-            var result = str.AsSpan().LeftPart(needle).ToString();
-            Assert.Equal(expectedResult, result);
-        }
-
-        [Theory]
-        [InlineData("", "", "")]
-        [InlineData("", "q", "")]
-        [InlineData("Banana split", "", "")]
-        [InlineData("Banana split", " ", "Banana")]
-        [InlineData("Banana split test", " split", "Banana")]
-        public void LeftPart_ValidArgsWithoutStringComparison_Correct(string str, string needle, string expectedResult)
-        {
-            var result = str.AsSpan().LeftPart(needle).ToString();
-            Assert.Equal(expectedResult, result);
-        }
-
-        [Theory]
-        [InlineData("", "", StringComparison.Ordinal, "")]
-        [InlineData("Banana split", " ", StringComparison.Ordinal, "Banana")]
-        [InlineData("Banana split test", " split", StringComparison.Ordinal, "Banana")]
-        [InlineData("Banana split test", " Split", StringComparison.Ordinal, "Banana split test")]
-        [InlineData("Banana split test", " Splït", StringComparison.InvariantCultureIgnoreCase, "Banana split test")]
-        public void LeftPart_ValidArgs_Correct(string str, string needle, StringComparison stringComparison, string expectedResult)
-        {
-            var result = str.AsSpan().LeftPart(needle, stringComparison).ToString();
-            Assert.Equal(expectedResult, result);
-        }
-    }
-}