# v91 — Worth It

<div align="left"><figure><img src="https://3495989837-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FE5Ketpww1s7TauSAJrJ8%2Fuploads%2FqvsOwNffasRmdwG55JV7%2Fimage.png?alt=media&#x26;token=b94ebcdf-3e78-4855-af61-06c41df5ff15" alt=""><figcaption></figcaption></figure></div>

## Features

* Professional license and subscription management as well as self-service payment possibility (via Stripe integration)
* New multi-fields feature for [Timeseries Database](https://docs.heisenware.com/app-builder/build-backend/functions-library/storage/timeseries-database)
* App Builder performance tuning, especially when reloading the browser page
* Slimmed-down [Docker agent](https://docs.heisenware.com/app-builder/build-backend/functions-library/agents/docker-agent) capable of running on resource-limited edge devices and IoT gateways
* New `Duration` and `Interval` objects for [Javascript Modifier](https://docs.heisenware.com/app-builder/build-backend/modifier#javascript-expressions)

## Fixes

* Widget transformation under zooming and extended page height works now
* Fixed wrong auto-page-switching after fresh deploy
* Fixed a race condition leading to zombie-subscriptions on the broker that led to performance issues
* Fixed CSS `z-index` issue leading to widgets overflowing the bottom navigation bar
* Fixed subscription losses on event-style functions when the underlying agent encountered network re-connects