src/vs/platform/userDataSync/common/userDataSyncService.ts/UserDataSyncService/applyManualSync
class UserDataSyncService:	private async applyManualSync(manifest: IUserDataManifest | null, executionId: string, token: CancellationToken): Promise<void> {
		const profileSynchronizers = this.getActiveProfileSynchronizers();
		for (const profileSynchronizer of profileSynchronizers) {
			if (token.isCancellationRequested) {
				return;
			}
			await profileSynchronizer.apply(executionId, token);
		}

		const defaultProfileSynchronizer = profileSynchronizers.find(s => s.profile.isDefault);
		if (!defaultProfileSynchronizer) {
			return;
		}

		const userDataProfileManifestSynchronizer = defaultProfileSynchronizer.enabled.find(s => s.resource === SyncResource.Profiles);
		if (!userDataProfileManifestSynchronizer) {
			return;
		}

		// Sync remote profiles which are not synced locally
		const remoteProfiles = (await (userDataProfileManifestSynchronizer as UserDataProfilesManifestSynchroniser).getRemoteSyncedProfiles(manifest?.latest ?? null)) || [];
		const remoteProfilesToSync = remoteProfiles.filter(remoteProfile => profileSynchronizers.every(s => s.profile.id !== remoteProfile.id));
		if (remoteProfilesToSync.length) {
			await this.syncRemoteProfiles(remoteProfilesToSync, manifest, false, executionId, token);
		}
	}