[appsuite-announce] Open-Xchange releases OX App Suite v8.51

[Open-Xchange App Suite Maintenance Announcements]

Dear Customers of Open-Xchange,

This release adds new ways to organize; contacts, plan work across Mail, Calendar, and Tasks, and manage email signatures centrally, while also improving performance, security, and everyday usability throughout OX App Suite.

- Private appointments by default: Users can now mark new appointments as private by default for their own calendars, making it easier to protect calendar details consistently.

- Resizable all-day area in Calendar: In day and week views, desktop users can now resize the all-day section when many all-day appointments need more space.

- Tasks in the calendar: Users can now show tasks with due dates directly in Calendar. The new Tasks calendar can be enabled in Calendar settings and shown or hidden like any other calendar.

- More context for shared and delegated tasks: Task details now show who created a task when it was created by someone else, for example in shared task lists or delegated task workflows.

- Choose where new contacts are saved: The contact creation dialogue now includes a “Save in” picker, allowing users to choose the private, public, or shared address book where a new contact should be stored.

- More flexible scheduled sending: Scheduled send now offers additional quick options for afternoon and evening, alongside the existing morning options. Scheduled messages are queued within a short time window, helping distribute delivery more evenly.

- Additionally, this OX App Suite release contains bug fixes and several improvements. A full list can be found here: https://documentation.open-xchange.com/appsuite/releases/8.51/changelogs/ui.html and https://documentation.open-xchange.com/appsuite/releases/8.51/changelogs/middleware.html

General Information and Breaking Changes

- This release includes a new update task. More information can be found here: https://documentation.open-xchange.com/appsuite/releases/8.51/noteworthy/00_index.html#scr-1718

- Java 25 — virtual-thread HTTP worker pool and opt-in generational ZGC: The core middleware now runs on Java 25 with virtual-thread HTTP workers enabled by default. More information can be found here: https://documentation.open-xchange.com/appsuite/releases/8.51/noteworthy/middleware.html#scr-1723

- Pre-Information: LTS releases are supported until the next LTS 'plus six months' to give enough time to schedule, test and rollout the upgrade. Please note, with the official launch of OX App Suite v8.47 LTS in March, OX App Suite v8.35 LTS will be officially supported until September 30, 2026. You will find a summary of all key features, important changes and an upgrade guide for moving from OX App Suite v8.35 LTS to OX App Suite v8.47 LTS here: https://documentation.open-xchange.com/appsuite/releases/lts/8.47/noteworthy/01_features-since-8.35.html

Fixes, software change requests, update tasks and further details to OX App Suite in this release include:
- https://documentation.open-xchange.com/appsuite/releases/8.51/

Shipped versions with latest Helm Chart v8.51.763:
- Open-Xchange App Suite Frontend v8.51.1
- Open-Xchange App Suite Middleware (Backend) v8.51.119

Technical Documentation, Deployment Information, Requirements and Support Commitment

For details of how to install and update OX App Suite v8, please refer to the instructions provided at: https://documentation.open-xchange.com/appsuite/operation-guides/

Best Regards,
Your Open-Xchange Team

-------------------------------------------------------------------------------------
Open-Xchange AG, Erftstraße 15–17, 50672 Cologne, District Court Cologne HRB 95366
Managing Board: Andreas Gauger, Dirk Valbert
Chairman of the Board: Dr. Paul-Josef Patt

European Office:
Open-Xchange GmbH, Olper Huette 3, D-57462 Olpe, Germany, District Court Siegen, HRB 8718
Managing Director: Manuel Engel

US Office: 
Open-Xchange Inc., 3000 El Camino Real, Building 4, Suite 200, Palo Alto, CA 94306, USA
-------------------------------------------------------------------------------------