As far as I'm aware you can't achieve that in cloud due the fact that atlassian does not allow customizations in their environment like you can do it with server .
You can raise a support case to atlassian at https://support.atlassian.com to confirm, however I'm pretty sure there's no way to get that.
Thanks and Regards,
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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