Do you have the curl php extension? If so, are the any other php or apache error messages? If you have curl and it's still not working then it will be difficult for me to debug without replicating your exact setup. Both the original socket method and the curl method work for me so I am not able to reproduce the issue in order to zero in on the problem. Tomorrow I'll try using PHP 7.3, but I doubt that is the issue - will let you know. I will post your issue to the dev list as well to see if any one else might be familiar with this kind of issue.
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