diff --git a/src/vs/workbench/api/browser/mainThreadDialogs.ts b/src/vs/workbench/api/browser/mainThreadDialogs.ts
index ff3b66e935d9a4a165b695168a21ffe5b8a337b3..938cb20c18bf0d94b231031359a7aa9fafc8320f 100644
--- a/src/vs/workbench/api/browser/mainThreadDialogs.ts
+++ b/src/vs/workbench/api/browser/mainThreadDialogs.ts
@@ -38,7 +38,8 @@ export class MainThreadDialogs implements MainThreadDiaglogsShape {
 			canSelectFolders: options?.canSelectFolders,
 			canSelectMany: options?.canSelectMany,
 			defaultUri: options?.defaultUri ? URI.revive(options.defaultUri) : undefined,
-			title: options?.title || undefined
+			title: options?.title || undefined,
+			availableFileSystems: []
 		};
 		if (options?.filters) {
 			result.filters = [];