Hi @lijiuri
I believe this event sales_order_shipment_track_save_after will work for you. You need to create an observer for this event. You need to create a Module inside your app/local directory.
You can create a observer file like this:
\app\code\local\vendorNamr\packageName\Model\Observer.php
Here is an example for create an observer in Magento 1.9
I hope it will help you.
Thanks
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