diff --git a/src/Docfx.MarkdigEngine.Extensions/ExtensionsHelper.cs b/src/Docfx.MarkdigEngine.Extensions/ExtensionsHelper.cs
index 1833039ac16..2a47f838972 100644
--- a/src/Docfx.MarkdigEngine.Extensions/ExtensionsHelper.cs
+++ b/src/Docfx.MarkdigEngine.Extensions/ExtensionsHelper.cs
@@ -139,7 +139,7 @@ public static void SkipWhitespace(ref StringSlice slice)
         }
     }
 
-    public static string TryGetStringBeforeChars(IEnumerable<char> chars, ref StringSlice slice, bool breakOnWhitespace = false)
+    public static string TryGetStringBeforeChars(IReadOnlyList<char> chars, ref StringSlice slice, bool breakOnWhitespace = false)
     {
         StringSlice savedSlice = slice;
         var c = slice.CurrentChar;
@@ -239,11 +239,11 @@ private static bool MatchPath(ref StringSlice slice, ref string path)
         string includedFilePath;
         if (slice.CurrentChar == '<')
         {
-            includedFilePath = TryGetStringBeforeChars(new char[] { ')', '>' }, ref slice, breakOnWhitespace: true);
+            includedFilePath = TryGetStringBeforeChars([')', '>'], ref slice, breakOnWhitespace: true);
         }
         else
         {
-            includedFilePath = TryGetStringBeforeChars(new char[] { ')' }, ref slice, breakOnWhitespace: true);
+            includedFilePath = TryGetStringBeforeChars([')'], ref slice, breakOnWhitespace: true);
         }
 
         if (includedFilePath == null)
@@ -264,7 +264,7 @@ private static bool MatchPath(ref StringSlice slice, ref string path)
         }
         else
         {
-            var title = TryGetStringBeforeChars(new char[] { ')' }, ref slice, breakOnWhitespace: false);
+            var title = TryGetStringBeforeChars([')'], ref slice, breakOnWhitespace: false);
             if (title == null)
             {
                 return false;
diff --git a/src/Docfx.MarkdigEngine.Extensions/Noloc/NolocParser.cs b/src/Docfx.MarkdigEngine.Extensions/Noloc/NolocParser.cs
index b7dfa65b018..12447ff19bd 100644
--- a/src/Docfx.MarkdigEngine.Extensions/Noloc/NolocParser.cs
+++ b/src/Docfx.MarkdigEngine.Extensions/Noloc/NolocParser.cs
@@ -24,7 +24,7 @@ public override bool Match(InlineProcessor processor, ref StringSlice slice)
             return false;
         }
 
-        var text = ExtensionsHelper.TryGetStringBeforeChars(new char[] { '\"', '\n' }, ref slice);
+        var text = ExtensionsHelper.TryGetStringBeforeChars(['\"', '\n'], ref slice);
 
         if (text == null || text.Contains('\n'))
         {