We're making changes to our HTTP/1.0 and HTTP/1.1 request handling to improve security and compliance with web standards. Starting August 1, 2025, all POST requests to Shopify APIs must include either a Content-Length header or Transfer-Encoding: chunked header, or they'll return an HTTP 411 error.
This is a companion discussion topic for the original entry at https://shopify.dev/changelog/deprecation-of-post-requests-without-a-content-length-or-transfer-encoding-chunked-header