Workflow tab is empty after Serial workflow is cancelled

1. install 8.10
2. create a File document
3. start a Serial workflow
4. assign it to the Administrator
5. in the task click Cancel
6. this displays an empty tab (see emptyWorkflowTab.png)
7. try to change tab does not make the tab disappear although it is not possible to switch back to the workflow tab unless starting a new one

Note: the behavior is similar to NXP-23445.