Апдейтну топик, вот какой post запрос идет при авторизации, проблема как раз с передачей json, тут он передается то ли хэш функцией, то ли как-то еще и в ответах я его найти не смог:
POST /events HTTP/1.1
Host: d2o5idwacg3gyw.cloudfront.net
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 Edge/18.18312
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.8,ru;q=0.7,ro-RO;q=0.5,ro;q=0.3,az-Latn;q=0.2
Referer:
https://signin.ebay.com/ws/eBayISAPI.dll?SignIn&lgout=1
Content-Type: text/plain; charset=UTF-8
Origin:
https://signin.ebay.com
Connection: keep-alive
Accept-Encoding: gzip, deflate
Content-Length: 753
{"user":[[{"data":"lvBkrk7kdktdBAvALKVafa0ky2jbSy+ETKbpaDRap2m6atzgt7amkabLaYb2iPhab2kK7aCfgRBaaizBcRKTAsbxJaAAaU+u2RBa7BPaQeBa1+hajFpaMcbaAaKTKSBQzRK5L7bKEaIg-yVH2KsV19hlHBTkaqBkRNfgpcyb$NjxkaJaHedAR6LjA6Lla9LkaewQTa0Lc-JBTKuxc6aUpN48NIvkHRaA+kzaI-3U++a2B2pmHbuaBifaHpFamlbBtEAF-6apgNlUEzNkv2emGeh3Bkb3ackaK$TamUgLIIh8vzZNAzZ6Gs2RTpLjvcj8n$$SAO9pen2aoYUByT7FdVBFbLbym$BKKyHaRM0rAnSlTQIbLcaayiVwPmU28UEpaKAIBaeolgaaI0cVVPYamqqERzM0Saa0L0SaABaK8yKGxdCDkTamO-RFbjvl5sTcFF3eLJaC5sSAkTSS$JaKoen5v0k-sFzI5xBPPxhgSLgXVL-k9RA97u9besBYLaIFT2FOAFO-TTgDTlKSIvtfHCPaQyBIKKbV9-T+EAacAFyK2cJd$ukx3+YA9PR66R-Y7TBcdyuTLC2syzg8erPqRzBF7Tch2632eR6mokTmAkj","user_id":"2f7b971408124f9f8d64953d3c24edeb"}]],"bcn":"bc18ae60-6f77-484c-9b29-ef6ffaf3e5d2","si":"adf0901f1861"}