@avigdors , Based on my check, when we choose LOB and click upload package File, it will get some js files and upload the package file by posting to https://endpoint.microsoft.com/api/extensiontelemetry with the payload as below:
To check on your side, you can click "F12" to open DevTools on Edge to check the detailed request action when we click upload package file.
If you have more questions on this, you can contact our Premier support to get more help.
Thanks for your understanding and have a nice day!
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