There are currently three known issues affecting workstep locks in Mosaic. Please read each scenario carefully, as the cause and resolution are different in each case.

Mosaic has always prevented users from opening more than one editable workstep at the same time. However, as of version 25.2, an additional control was introduced to support users working in Evo, where Mosaic can be open in multiple Evo tabs at once — making it possible to bypass this restriction by opening worksteps from different Evo tabs.

If a user closes a workstep incorrectly — for example, by clicking the browser's X button rather than closing the workstep properly within Mosaic — a lock is left on that workstep. From version 25.2, that lock prevents the user from opening any other workstep until it is resolved. In previous versions of Mosaic, an incorrect close would only lock that one specific step.

Any user who closes a workstep using the browser's X button or another method that does not properly close the workstep within Mosaic.

The most important thing users can do to prevent this issue is to always close worksteps correctly within Mosaic, rather than using the browser's X button.

To resolve an existing lock, there are several options depending on your system settings:

📌 Note: Users should only remove a lock when they are certain the workstep is no longer open elsewhere. Please ensure your workers are aware of this option and understand when it is appropriate to use it.

Mosaic uses the browser unload event when pages close to release resources such as locks. This event is being deprecated by Chrome and Edge during 2026 — the deprecation is being rolled out gradually and is currently affecting only a small number of users. By 22 September 2026, the change will apply to all Chrome and Edge users.

When a user is affected, closing a workstep correctly removes the lock from the Mosaic database as expected — but the browser retains a local record that continues to block the user from opening another workstep, even though they closed it correctly. Because this is held in the browser rather than the database, it will not appear in Lock Manager.

Users on Chrome or Edge browser versions where the deprecation has already been rolled out. This will affect an increasing number of users over time, reaching all Chrome and Edge users by 22 September 2026.

The following upcoming releases will remove the dependency on the unload event and switch to a supported alternative:

In the meantime, there are two options your IT team can apply to delay the impact for any affected users:

📌 Note: Wildfly customers only — where an urgent fix is needed, we are able to run a script to force the browser to delay the deprecation. This will be run only where other workarounds cannot be used.

If a user is already affected, logging out of Mosaic and logging back in may temporarily resolve the issue.

Some users may notice that a Case Chronology record appears locked after closing the Case Chronology window. This lock applies to the Case Chronology only and does not prevent users from accessing other areas of Mosaic.

Please wait 30 seconds. The lock will clear automatically and the user will be able to continue as normal.

📌 Note: A fix for this issue is included in the 26.1.1.0 patch release, due in the next few weeks.