Switching between tabs in the dashboard updates produces a session not available warning message

Upon switching the dashboard update tabs the following warning appears in logs.

The following is thrown in logs:

WARN [TP-Processor6] [atlassian.confluence.user.UserInterfaceState] putInSession Unable to save preference confluence.recentchanges.size in session: session not available
- referer: https://base_URL/dashboard.action | url: /rest/dashboardmacros/1.0/updates | userName: username

As far as I know this warning doesn't cause any problem to Confluence ,but this is something we should investigate.

Workaround : Change the log4j.properties file to add the line log4j.logger.atlassian.confluence.user.UserInterfaceState=ERROR
This should suppress the warning message.