diff --git a/src/Umbraco.Tests.UnitTests/Umbraco.Core/Configuration/Models/RequestHandlerSettingsTests.cs b/src/Umbraco.Tests.UnitTests/Umbraco.Core/Configuration/Models/RequestHandlerSettingsTests.cs
new file mode 100644
index 0000000000..c16d9b4897
--- /dev/null
+++ b/src/Umbraco.Tests.UnitTests/Umbraco.Core/Configuration/Models/RequestHandlerSettingsTests.cs
@@ -0,0 +1,90 @@
+using System.Linq;
+using NUnit.Framework;
+using Umbraco.Cms.Core.Configuration.Models;
+using Umbraco.Cms.Core.Configuration.UmbracoSettings;
+
+namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.Configuration.Models
+{
+    [TestFixture]
+    public class RequestHandlerSettingsTests
+    {
+        [Test]
+        public void Given_CharCollection_With_DefaultEnabled_MergesCollection()
+        {
+            var userCollection = new CharacterReplacement[]
+            {
+                new() { Char = "test", Replacement = "replace" },
+                new() { Char = "test2", Replacement = "replace2" }
+            };
+
+
+            var settings = new RequestHandlerSettings { CharCollection = userCollection };
+            var actual = settings.GetCharReplacements().ToList();
+
+            var expectedCollection = RequestHandlerSettings.DefaultCharCollection.ToList();
+            expectedCollection.AddRange(userCollection);
+
+            Assert.AreEqual(expectedCollection.Count, actual.Count);
+            Assert.That(actual, Is.EquivalentTo(expectedCollection));
+        }
+
+        [Test]
+        public void Given_CharCollection_With_DefaultDisabled_ReturnsUserCollection()
+        {
+            var userCollection = new CharacterReplacement[]
+            {
+                new() { Char = "test", Replacement = "replace" },
+                new() { Char = "test2", Replacement = "replace2" }
+            };
+
+            var settings = new RequestHandlerSettings { CharCollection = userCollection, EnableDefaultCharReplacements = false };
+            var actual = settings.GetCharReplacements().ToList();
+
+            Assert.AreEqual(userCollection.Length, actual.Count);
+            Assert.That(actual, Is.EquivalentTo(userCollection));
+        }
+
+        [Test]
+        public void Given_CharCollection_That_OverridesDefaultValues_ReturnsReplacements()
+        {
+            var userCollection = new CharacterReplacement[]
+            {
+                new() { Char = "%", Replacement = "percent" },
+                new() { Char = ".", Replacement = "dot" }
+            };
+
+            var settings = new RequestHandlerSettings { CharCollection = userCollection };
+            var actual = settings.GetCharReplacements().ToList();
+
+            Assert.AreEqual(RequestHandlerSettings.DefaultCharCollection.Length, actual.Count);
+
+            Assert.That(actual, Has.Exactly(1).Matches<CharacterReplacement>(x => x.Char == "%" && x.Replacement == "percent"));
+            Assert.That(actual, Has.Exactly(1).Matches<CharacterReplacement>(x => x.Char == "." && x.Replacement == "dot"));
+            Assert.That(actual, Has.Exactly(0).Matches<CharacterReplacement>(x => x.Char == "%" && x.Replacement == string.Empty));
+            Assert.That(actual, Has.Exactly(0).Matches<CharacterReplacement>(x => x.Char == "." && x.Replacement == string.Empty));
+        }
+
+        [Test]
+        public void Given_CharCollection_That_OverridesDefaultValues_And_ContainsNew_ReturnsMergedWithReplacements()
+        {
+            var userCollection = new CharacterReplacement[]
+            {
+                new() { Char = "%", Replacement = "percent" },
+                new() { Char = ".", Replacement = "dot" },
+                new() {Char = "new", Replacement = "new"}
+            };
+
+            var settings = new RequestHandlerSettings { CharCollection = userCollection };
+            var actual = settings.GetCharReplacements().ToList();
+
+            // Add 1 to the length, because we're expecting to only add one new one
+            Assert.AreEqual(RequestHandlerSettings.DefaultCharCollection.Length + 1, actual.Count);
+
+            Assert.That(actual, Has.Exactly(1).Matches<CharacterReplacement>(x => x.Char == "%" && x.Replacement == "percent"));
+            Assert.That(actual, Has.Exactly(1).Matches<CharacterReplacement>(x => x.Char == "." && x.Replacement == "dot"));
+            Assert.That(actual, Has.Exactly(1).Matches<CharacterReplacement>(x => x.Char == "new" && x.Replacement == "new"));
+            Assert.That(actual, Has.Exactly(0).Matches<CharacterReplacement>(x => x.Char == "%" && x.Replacement == string.Empty));
+            Assert.That(actual, Has.Exactly(0).Matches<CharacterReplacement>(x => x.Char == "." && x.Replacement == string.Empty));
+        }
+    }
+}
diff --git a/src/Umbraco.Tests.UnitTests/Umbraco.Core/ShortStringHelper/DefaultShortStringHelperTestsWithoutSetup.cs b/src/Umbraco.Tests.UnitTests/Umbraco.Core/ShortStringHelper/DefaultShortStringHelperTestsWithoutSetup.cs
index 6f9ee481cc..5aa8198e07 100644
--- a/src/Umbraco.Tests.UnitTests/Umbraco.Core/ShortStringHelper/DefaultShortStringHelperTestsWithoutSetup.cs
+++ b/src/Umbraco.Tests.UnitTests/Umbraco.Core/ShortStringHelper/DefaultShortStringHelperTestsWithoutSetup.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
+using System;
 using System.Diagnostics;
 using System.Linq;
 using System.Text;
@@ -19,7 +20,7 @@ namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.ShortStringHelper
         {
             var requestHandlerSettings = new RequestHandlerSettings()
             {
-                CharCollection = Enumerable.Empty<IChar>(),
+                CharCollection = Array.Empty<CharacterReplacement>(),
                 ConvertUrlsToAscii = "false"
             };
 
@@ -45,7 +46,7 @@ namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.ShortStringHelper
         {
             var requestHandlerSettings = new RequestHandlerSettings()
             {
-                CharCollection = Enumerable.Empty<IChar>(),
+                CharCollection = Array.Empty<CharacterReplacement>(),
                 ConvertUrlsToAscii = "false"
             };
 
@@ -339,7 +340,7 @@ namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.ShortStringHelper
         {
             var requestHandlerSettings = new RequestHandlerSettings()
             {
-                CharCollection = Enumerable.Empty<IChar>(),
+                CharCollection = Array.Empty<CharacterReplacement>(),
                 ConvertUrlsToAscii = "false"
             };