3235039 - HTTP Connection broken and HTTP_1_1_REQUIRED

During a HTTP destination connection test, Status HTTP Response 500 – Connection Broken error occurs.

On dev_icm logs, there is the following entries:

Image/data in this KBA is from SAP internal systems, sample data, or demo systems. Any resemblance to real data is purely coincidental.

(...)

[Thr <thread_number>] Error Code: 13 (HTTP_1_1_REQUIRED)

(...)

[Thr <thread_number>]   HTTP/1.0 500 Connection broken  

(...)

SAP Kernel < 789

HTTP 500 Connection Broken, HTTP_1_1_REQUIRED, Error Code 13, HTTP/2 , KBA , BC-CST-IC , Internet Communication Manager , Problem