There are two aspects:

• stale UI's are cleared out as a side effect when the re-loaded UI is created. We call {{ getBeanStore(UiContextReference.ofCurrentUi()).clear()}} -> which will clear out the new UI's bean store. Explicit UI reference should be used.
• the refreshed UI apparently has the same embed ID as the old one and since the embed ID is used as unique identifier of the UI - again, the new UI will get cleared out. We should complement the embed ID with the ui ID (spinner for every Vaadin session).