Problem/Motivation
When running a batch process on a Drupal site which is behind a F5 Web Application firewall, this triggers an "HTTP protocol compliance failed" violation.
As stated on https://support.f5.com/csp/article/K10280, the violation is triggered by a POST request with Content-Length: 0.
Steps to reproduce
Run a batch job on a Drupal website which is behind a F5 WAF.
Proposed resolution
As there is no real data needed to be posted, add some dummy data to the post so content-Length > 0. See the attached patches.