diff --git a/src/Fable.Transforms/Replacements.fs b/src/Fable.Transforms/Replacements.fs
index 602d4d50ee..92c9fdd6f2 100644
--- a/src/Fable.Transforms/Replacements.fs
+++ b/src/Fable.Transforms/Replacements.fs
@@ -2550,6 +2550,7 @@ let strings
         | [ ExprType String ]
         | [ ExprType Char; ExprType(Number(Int32, NumberInfo.Empty)) ]
         | [ ExprType String; ExprType(Number(Int32, NumberInfo.Empty)) ]
+        | [ ExprType String; StringComparisonEnumValue ]
         | [ ExprType String
             ExprType(Number(Int32, NumberInfo.Empty))
             StringComparisonEnumValue ] ->
diff --git a/tests/Js/Main/StringTests.fs b/tests/Js/Main/StringTests.fs
index 674077d266..a7c7eb271c 100644
--- a/tests/Js/Main/StringTests.fs
+++ b/tests/Js/Main/StringTests.fs
@@ -720,6 +720,10 @@ let tests =
             |> equal 4
 
       testCase "String.IndexOf with StringComparison" <| fun () ->
+            "abcdbc".IndexOf("b", StringComparison.Ordinal)
+            |> equal 1
+
+      testCase "String.IndexOf with index and StringComparison" <| fun () ->
             "abcdbc".IndexOf("b", 3, StringComparison.Ordinal)
             |> equal 4
 
@@ -732,6 +736,10 @@ let tests =
             |> equal 1
 
       testCase "String.LastIndexOf with StringComparison" <| fun () ->
+            "abcdbc".LastIndexOf("b", StringComparison.Ordinal)
+            |> equal 4
+
+      testCase "String.LastIndexOf with index and StringComparison" <| fun () ->
             "abcdbc".LastIndexOf("b", 3, StringComparison.Ordinal)
             |> equal 1