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Popup URL / App allows you to open an application or a web page upon receiving or placing a call and pass parameters (static parameters or supported variables). To add it, go to Collaboration Settings -> Personal -> Popup URL / App (it can also be added via WMS -> Users -> Edit preferences -> Settings -> Callback URLs).
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App
You can set up the popup URL / App to be for incoming / outgoing call and select the triggering event:
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