src/vs/platform/userDataSync/common/abstractSynchronizer.ts/AbstractSynchroniser/preview
class AbstractSynchroniser:	async preview(manifest: IUserDataResourceManifest | null, userDataSyncConfiguration: IUserDataSyncConfiguration, headers: IHeaders = {}): Promise<ISyncResourcePreview | null> {
		return this._sync(manifest, false, userDataSyncConfiguration, headers);
	}