[oxse-announce] Open-Xchange releases OX App Suite v8.53

[Open-Xchange Server Edition Maintenance Announcements]

Dear Customers of Open-Xchange,

This release introduces enhanced collaboration capabilities, including support for multiple calendars within shared accounts and the expansion of cross-context sharing to include mail, deputies, and "send-on-behalf" functionality.

- Multiple calendars per shared account: A shared account can now hold more than one calendar, all listed under “Shared accounts” — the default one under the account name, additional calendars as “account: calendar”. New calendars are created from the default calendar's context menu, appointments can be moved between calendars of the same account, and the usual calendar permissions apply throughout. More information can be found here: https://documentation.open-xchange.com/8/middleware/permissions_and_capabilities/shared_accounts.html 

- Cross-context sharing extended to mail and deputies: Building on the cross-context collaboration introduced in v8.52, mail and calendar folders can be shared with users of another context, deputies appointed for them, and mail sent on their behalf; those users appear in autocomplete and in all address pickers. Each module is gated separately. See the feature documentation for further details: https://documentation.open-xchange.com/8/middleware/permissions_and_capabilities/cross_context_collaboration.html 

- 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/8.53/changelogs/ui.html and https://documentation.open-xchange.com/appsuite/releases/8.53/changelogs/middleware.html

General Information and Breaking Changes

- This release includes an update task. More information can be found here: https://documentation.open-xchange.com/appsuite/releases/8.53/noteworthy/00_index.html#scr-1853 

- External images in mail now load in the browser, and the server-side image proxy is off by default. Security is unchanged — a strict policy on the mail view improves this feature. One thing may need your attention: if your deployment relied on the proxy to hide users' IP addresses from senders, this would need to be re-enabled. (see instructions at the end of this section), knowing that proxied images might fail to load. More information can be found here: https://documentation.open-xchange.com/appsuite/releases/8.53/noteworthy/00_index.html#external-images-in-mail-load-directly 

- 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/8.53/

Shipped versions with latest Helm Chart v8.53.1045:
- Open-Xchange App Suite Frontend v8.53.1
- Open-Xchange App Suite Middleware (Backend) v8.53.297

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
-------------------------------------------------------------------------------------