diff --git a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerConfigOptions.cs b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerConfigOptions.cs
index de28960da246e3758fd5174ca32de994873c1b60..2fd6e9fc059897b938b935e205a29d3a8e3135bd 100644
--- a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerConfigOptions.cs
+++ b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerConfigOptions.cs
@@ -3,6 +3,7 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 
@@ -22,11 +23,6 @@ public abstract class AnalyzerConfigOptions
         /// Get an analyzer config value for the given key, using the <see cref="KeyComparer"/>.
         /// </summary>
         public abstract bool TryGetValue(string key, out string value);
-
-        /// <summary>
-        /// Get the keys of the defined options.
-        /// </summary>
-        public abstract IEnumerable<string> Keys { get; }
     }
 
     internal sealed class CompilerAnalyzerConfigOptions : AnalyzerConfigOptions
@@ -41,7 +37,5 @@ public CompilerAnalyzerConfigOptions(ImmutableDictionary<string, string> propert
         }
 
         public override bool TryGetValue(string key, out string value) => _backing.TryGetValue(key, out value);
-
-        public override IEnumerable<string> Keys => _backing.Keys;
     }
 }
diff --git a/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt b/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
index 1050be2d7662b955e45c52cbd95b3fdc3234f478..d76a01da73e02821920f3a36f3c894d9596cb5e1 100644
--- a/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
+++ b/src/Compilers/Core/Portable/PublicAPI.Unshipped.txt
@@ -21,7 +21,6 @@ Microsoft.CodeAnalysis.SarifVersion.Latest = 2147483647 -> Microsoft.CodeAnalysi
 Microsoft.CodeAnalysis.SarifVersion.Sarif1 = 1 -> Microsoft.CodeAnalysis.SarifVersion
 Microsoft.CodeAnalysis.SarifVersion.Sarif2 = 2 -> Microsoft.CodeAnalysis.SarifVersion
 Microsoft.CodeAnalysis.SarifVersionFacts
-abstract Microsoft.CodeAnalysis.Diagnostics.AnalyzerConfigOptions.Keys.get -> System.Collections.Generic.IEnumerable<string>
 Microsoft.CodeAnalysis.SymbolDisplayMiscellaneousOptions.IncludeNotNullableReferenceTypeModifier = 256 -> Microsoft.CodeAnalysis.SymbolDisplayMiscellaneousOptions
 static Microsoft.CodeAnalysis.SarifVersionFacts.TryParse(string version, out Microsoft.CodeAnalysis.SarifVersion result) -> bool
 Microsoft.CodeAnalysis.IMethodSymbol.IsConditional.get -> bool
diff --git a/src/Workspaces/Core/Portable/Options/EditorConfig/EditorConfigStorageLocationExtensions.cs b/src/Workspaces/Core/Portable/Options/EditorConfig/EditorConfigStorageLocationExtensions.cs
index 5abc812cba2cf8d6d834b9d24f707d32bf89d4ba..5423c11c4e401904a352ea5aedcd8ea586e69a40 100644
--- a/src/Workspaces/Core/Portable/Options/EditorConfig/EditorConfigStorageLocationExtensions.cs
+++ b/src/Workspaces/Core/Portable/Options/EditorConfig/EditorConfigStorageLocationExtensions.cs
@@ -1,9 +1,8 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Immutable;
+using System.Collections.Generic;
 using Microsoft.CodeAnalysis.Diagnostics;
-using Roslyn.Collections.Immutable;
 
 namespace Microsoft.CodeAnalysis.Options
 {
@@ -11,15 +10,17 @@ internal static class EditorConfigStorageLocationExtensions
     {
         public static bool TryGetOption(this IEditorConfigStorageLocation editorConfigStorageLocation, AnalyzerConfigOptions analyzerConfigOptions, Type type, out object value)
         {
-            var optionDictionary = analyzerConfigOptions.Keys.ToImmutableDictionary(
-                key => key,
-                key =>
-                {
-                    analyzerConfigOptions.TryGetValue(key, out var optionValue);
-                    return optionValue;
-                });
+            // This is a workaround until we have an API for enumeratings AnalyzerConfigOptions.
+            var backingField = analyzerConfigOptions.GetType().GetField("_backing", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+            var backing = backingField?.GetValue(analyzerConfigOptions);
 
-            return editorConfigStorageLocation.TryGetOption(optionDictionary, type, out value);
+            if (backing is IReadOnlyDictionary<string, string> backingDictionary)
+            {
+                return editorConfigStorageLocation.TryGetOption(backingDictionary, type, out value);
+            }
+
+            value = null;
+            return false;
         }
     }
 }
diff --git a/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs b/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs
index e45f3f0b04c3501d053f00d63d382a4e31d9a0a0..962eb68f1a9859a2578627b7b21686b4d24dfdd9 100644
--- a/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs
+++ b/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs
@@ -319,8 +319,6 @@ public WorkspaceAnalyzerConfigOptions(AnalyzerConfigOptionsResult analyzerConfig
                 }
 
                 public override bool TryGetValue(string key, out string value) => _backing.TryGetValue(key, out value);
-
-                public override IEnumerable<string> Keys => _backing.Keys;
             }
         }