diff --git a/src/nunit.analyzers.tests/UpdateStringFormatToInterpolatableString/UpdateStringFormatToInterpolatableStringCodeFixTests.cs b/src/nunit.analyzers.tests/UpdateStringFormatToInterpolatableString/UpdateStringFormatToInterpolatableStringCodeFixTests.cs
index faf9fe7c..179f3103 100644
--- a/src/nunit.analyzers.tests/UpdateStringFormatToInterpolatableString/UpdateStringFormatToInterpolatableStringCodeFixTests.cs
+++ b/src/nunit.analyzers.tests/UpdateStringFormatToInterpolatableString/UpdateStringFormatToInterpolatableStringCodeFixTests.cs
@@ -56,11 +56,11 @@ public void ConvertWhenMinimumParametersIsTwo()
         {
             var code = TestUtility.WrapInTestMethod(@"
                 const int actual = 42;
-                ↓Assert.That(actual, Is.EqualTo(42), ""Expected actual value to be 42, but was: {0}"", actual);
+                ↓Assert.That(actual, Is.EqualTo(42), ""Expected actual value to be 42, but was: {0} at time {1:HH:mm:ss}"", actual, DateTime.Now);
             ");
             var fixedCode = TestUtility.WrapInTestMethod(@"
                 const int actual = 42;
-                Assert.That(actual, Is.EqualTo(42), $""Expected actual value to be 42, but was: {actual}"");
+                Assert.That(actual, Is.EqualTo(42), $""Expected actual value to be 42, but was: {actual} at time {DateTime.Now:HH:mm:ss}"");
             ");
             RoslynAssert.CodeFix(analyzer, fix, expectedDiagnostic, code, fixedCode);
         }
@@ -82,6 +82,31 @@ public void TestConvertWithEmbeddedSpecialCharacters(string text)
 
             RoslynAssert.CodeFix(analyzer, fix, expectedDiagnostic, code, fixedCode);
         }
+
+        [TestCase("")]
+        [TestCase(":N1")]
+        [TestCase(",5")]
+        [TestCase(",-5")]
+        [TestCase(",5:N1")]
+        public void TestFormatModifiers(string modifier)
+        {
+            string argument = "1.23";
+            var code = TestUtility.WrapInTestMethod($"↓Assert.Pass(\"{{0{modifier}}}\", {argument});");
+
+            var fixedCode = TestUtility.WrapInTestMethod($"Assert.Pass($\"{{{argument}{modifier}}}\");");
+
+            RoslynAssert.CodeFix(analyzer, fix, expectedDiagnostic, code, fixedCode);
+        }
+
+        [Test]
+        public void TestEscapedBraces()
+        {
+            var code = TestUtility.WrapInTestMethod("↓Assert.Pass(\"{{{0}}}\", 42);");
+
+            var fixedCode = TestUtility.WrapInTestMethod("Assert.Pass($\"{{{42}}}\");");
+
+            RoslynAssert.CodeFix(analyzer, fix, expectedDiagnostic, code, fixedCode);
+        }
     }
 }
 #endif
diff --git a/src/nunit.analyzers.tests/WithinUsage/WithinUsageAnalyzerTests.cs b/src/nunit.analyzers.tests/WithinUsage/WithinUsageAnalyzerTests.cs
index 7ec8a3df..6e0b7285 100644
--- a/src/nunit.analyzers.tests/WithinUsage/WithinUsageAnalyzerTests.cs
+++ b/src/nunit.analyzers.tests/WithinUsage/WithinUsageAnalyzerTests.cs
@@ -373,7 +373,7 @@ public void TestMethod()
         {{
             var instance = new UserDefinedType(1, 1.1, ""1.1"");
 
-            Assert.That(new UserDefinedType(1, 1.2, ""1.1""), Is.EqualTo(instance).Within(0.1));
+            Assert.That(new UserDefinedType(1, 1.2, ""1.1""), Is.EqualTo(instance).↓Within(0.1));
         }}
 
         private {kind} UserDefinedType
@@ -419,7 +419,7 @@ public void TestMethod()
         {
             var instance = new SomeRecord(1, 1.1, ""1.1"");
 
-            Assert.That(new SomeRecord(1, 1.2, ""1.1""), Is.EqualTo(instance).Within(0.1));
+            Assert.That(new SomeRecord(1, 1.2, ""1.1""), Is.EqualTo(instance).↓Within(0.1));
         }
 
         private sealed record SomeRecord
diff --git a/src/nunit.analyzers/Helpers/CodeFixHelper.cs b/src/nunit.analyzers/Helpers/CodeFixHelper.cs
index 4294c334..f1ac40a5 100644
--- a/src/nunit.analyzers/Helpers/CodeFixHelper.cs
+++ b/src/nunit.analyzers/Helpers/CodeFixHelper.cs
@@ -159,7 +159,7 @@ internal static IEnumerable<InterpolatedStringContentSyntax> UpdateStringFormatT
                             string formatClause = formatSpecification.Substring(++argumentFormatSpecification, argumentSpecificationEnd - argumentFormatSpecification);
                             interpolationFormat = SyntaxFactory.InterpolationFormatClause(
                                 SyntaxFactory.Token(SyntaxKind.ColonToken),
-                                SyntaxFactory.Literal(formatClause));
+                                InterpolatedStringTextToken(formatClause));
                         }
 
                         yield return SyntaxFactory.Interpolation(formatArgument, interpolationAlignment, interpolationFormat);
diff --git a/src/nunit.analyzers/Helpers/Constraints.cs b/src/nunit.analyzers/Helpers/Constraints.cs
index 1d070a6f..2dc94145 100644
--- a/src/nunit.analyzers/Helpers/Constraints.cs
+++ b/src/nunit.analyzers/Helpers/Constraints.cs
@@ -7,7 +7,7 @@ namespace NUnit.Analyzers.Helpers
 {
     internal sealed class Constraints
     {
-        public Constraints(string staticClass, string? modifier, string? constraintMethod, string? property1 = default, string? property2 = null)
+        public Constraints(string staticClass, string? modifier, string? constraintMethod, string? property1 = null, string? property2 = null)
         {
             this.StaticClass = staticClass;
             this.Modifier = modifier;