@patrickli This should be possible. Because when you click on a user in M365 - you can also click on "start a chat" - after that your browser for example edge or chrome is asking you with which application you want to open this link, for example in my environment I have also Cisco Jabber installed and the link was asking me for: Jabber or Teams. So it should be possible! There is in my opinion no reason why it should not work in other application if you find some who can code this.

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