Curl error 55 when trying to send a large POST body

Reproduction steps:

1. Open the attached “IN-131726” project
2. Open the “SampleScene”
3. Enter Play mode
4. Observe the Console window

Actual results: The following error appears: “Curl error 55: Sending data failed with unitytls error code 10” and “result = Error” is printed
Expected results: No errors appear and the POST is sent successfully, “result = success” is printed

Reproducible with: 60003.3f1
Not reproducible with: 6000.0.73f1, 6000.3.4f1, 6000.3.14f1, 6000.6.0a4

Reproducible on: Windows 11
Not reproducible on: macOS 26.4.1