After the call reaches, i want the screen pop to stay up for 30 seconds, even after the call is ended.
but if the second call comes ...the existing pop screen will be overcome by the new one
You are referring to the screen pop gadget correct?
The way that the gadget is written, the screen pop url is based off the call events, so if the call ends, it triggers the handleEndDialog. If you want the behavior that it stays up for 30 seconds, you will probably need a local map to keep track of what time the url pop can disappear and complete the action at the appropriate time. That is just a guess as I haven't tried it myself.
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