diff --git a/src/monaco.contribution.ts b/src/monaco.contribution.ts
index 1e122b9f..d5cf4f67 100644
--- a/src/monaco.contribution.ts
+++ b/src/monaco.contribution.ts
@@ -42,7 +42,7 @@ export class LanguageServiceDefaultsImpl implements monaco.languages.typescript.
 
 	addExtraLib(content: string, filePath?: string): IDisposable {
 		if (typeof filePath === 'undefined') {
-			filePath = `ts:extralib-${Date.now()}`;
+			filePath = `ts:extralib-${Math.random().toString(36).substring(2, 15)}`;
 		}
 
 		if (this._extraLibs[filePath]) {