Hi @Sébastien PAULET
According to the official documentation, shared channels are not currently supported for Dynamics 365 applications.
To get this feature more quickly, you can send a feedback directly to Microsoft Feedback to add it in future updates.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future.
Thanks for your understanding and support.
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