diff --git a/extensions/typescript-language-features/src/features/bufferSyncSupport.ts b/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
index 9dbdee511f2..faa6d7c483d 100644
--- a/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
+++ b/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
@@ -159,8 +159,7 @@ class SyncedBufferMap {
 	}
 
 	private toKey(resource: Uri): string | null {
-		const key = this._normalizePath(resource);
-		return key ? key.toLowerCase() : key;
+		return this._normalizePath(resource);
 	}
 }