I can't use the old editor.
There was information in the community that only Atlassian support engineers could make older editors available.
Please issue a ticket like the above user.
Welcome to the Community!
I've tagged your question so someone from Atlassian should see it, bear in mind though that it is New Year weekend.
In the mean time, have you tried the below article?
Hi Community! We're thrilled to share that Team Calendars for Confluence is now a built-in feature for Confluence Data Center releases 7.11 and beyond. A long time favorite, Team Cale...
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