Hi @Vedovi, Fabio (VisMederi Holding srl)
Welcome to our forum!
Shared calendars in New Outlook are not fully integrated. Based on my tests, clicking Accept and View Shared Calendar will be directed to the web client to view the shared calendar.
Please understand that New Outlook is currently in preview, and many features have not yet been designed. For your experience, consider switching back to the classic version.
Also, I searched the Outlook official feedback collection site and noticed that a similar idea had been posted and the Outlook team had marked the project as "we're considering this". For faster access to features, you can propose or vote for it in the feedback portal. Many features of our current products are designed and upgraded based on customers’ feedback. You can also make suggestions on that website and hope Microsoft will notice this in the future. Thank you for your understanding and support!
Hope this helps!
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