Release 8.53

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 ones 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.
• Cross-context sharing extended to mail and deputies: Building on the cross-context collaboration introduced in 8.52, 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.

A detailed list of changes can be found in the changelogs.

Technical documentation available at documentation.open-xchange.com/8.53.0

Expected release date: September 2026