I have not see a way to do this without perhaps modifying the source code but I have seen this question asked before. At this point I would recommend creating a Suggestion request on JAC. When you do please post the link here so the Community can vote on the issue.
In the meantime there may be third pary calendar add-ons that perform in this manner.
Hi all! My name is Miles and I work on the Marketplace team. We’re looking for better ways to recommend and suggest apps that are truly crowd favorites, so of course we wanted to poll the Community. ...
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