diff --git a/ICSharpCode.Decompiler.Tests/TestCases/Pretty/QueryExpressions.cs b/ICSharpCode.Decompiler.Tests/TestCases/Pretty/QueryExpressions.cs
index 160ef4a65..0870735b1 100644
--- a/ICSharpCode.Decompiler.Tests/TestCases/Pretty/QueryExpressions.cs
+++ b/ICSharpCode.Decompiler.Tests/TestCases/Pretty/QueryExpressions.cs
@@ -48,6 +48,10 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 		{
 			public Maybe<int> Value;
 
+#if CS60
+			public Maybe<int> this[int index] => default(Maybe<int>);
+#endif
+
 			public Func<Maybe<int>> Factory()
 			{
 				return () => default(Maybe<int>);
@@ -237,6 +241,11 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 		{
 			return holder?.Factory()().Where((int value) => value > 0).Select((int value) => value.ToString());
 		}
+
+		public Maybe<string>? NullConditionalIndexerQuery(MaybeHolder holder)
+		{
+			return holder?[0].Where((int value) => value > 0).Select((int value) => value.ToString());
+		}
 #endif
 
 		public static IEnumerable<char> Issue1310a(bool test)
diff --git a/ICSharpCode.Decompiler/CSharp/Transforms/IntroduceQueryExpressions.cs b/ICSharpCode.Decompiler/CSharp/Transforms/IntroduceQueryExpressions.cs
index d33e41884..4745061e3 100644
--- a/ICSharpCode.Decompiler/CSharp/Transforms/IntroduceQueryExpressions.cs
+++ b/ICSharpCode.Decompiler/CSharp/Transforms/IntroduceQueryExpressions.cs
@@ -380,7 +380,8 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 		bool IsNullConditional(Expression target) => target switch {
 			UnaryOperatorExpression { Operator: UnaryOperatorType.NullConditional } => true,
 			MemberReferenceExpression member => IsNullConditional(member.Target),
-			InvocationExpression { Target: { } invocationTarget } => IsNullConditional(invocationTarget),
+			InvocationExpression invocation => IsNullConditional(invocation.Target),
+			IndexerExpression { Target: { } indexerTarget } => IsNullConditional(indexerTarget),
 			_ => false
 		};