At the moment it just copies the passed resource request, but we need to make sure the http body is not copied, but the current preserved. This is important when using the network process to avoid sending the http body over the IPC.
This will be fixed by https://github.com/WebKit/WebKit/pull/10029
Fixed by 260252@main (ff7c488): https://commits.webkit.org/260252@main
<rdar://problem/105448089>