see #18852 (comment)
and #18852 (comment)

In #14858 we added a feature to define a config live_query_max_execution_time to limit the max time a live query is executed for. If someone is using the Visitor Profile widget in the Dashboard, and if this setting is configured, and if a query takes too long, it may result in an error being shown in the UI.

Expected: It would say "The request took too long to execute. Please try ..." or something similar instead of a generic error message.

Because the query is used to fetch a specific profile this should always be fairly fast so I don't assume it's a big problem and combination of the widget being used and this setting being configured etc be rare.