It may be the new Dashboard. It was published for Confluence 5.9 Server on 24th Nov 2015 (see all details here) - So Atlassian is probably upgrading it on all Cloud instances too.
Nic is right: If you had a custom dashboard (the dashboard can be redirected to the home page of a space), you can just use his link to restore the setting.
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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